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February 2009
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 Engineers at Goddard Space Flight Center in Greenbelt, Md., recently tested NASA's Solar Dynamics Observatory ( SDO) to determine its mass properties. SDO, the first mission of NASA's Living With a Star program, will study the sun's atmosphere in unprecedented detail to reveal how variations on the sun influence Earth and nearby space. For three days beginning on March 31, SDO sat on a slowly spinning " Miller Table" in the Spacecraft Checkout and Integration Area, a " clean room" at Goddard. Test engineers measured the spacecraft's mass, center of gravity, and moments and products of inertia to provide SDO's launch mass properties as accurately as possible. The moment of inertia describes how the spacecraft resists changes to its rate of rotation in each direction—important information to know prior to SDO's planned November launch. "This is the final verification test of the observatory before shipping," said Son N. Ngo, the SDO mechanical lead engineer. "The final data will be used to verify requirements for the launch vehicle." For more information about SDO, visit: http://sdo.gsfc.nasa.gov
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NASA has set media accreditation deadlines for the next space shuttle flight to the International Space Station. Shuttle Endeavour is targeted to launch June 13 to begin its mission, designated STS-127. The 16-day flight will deliver a new station crew member and will complete construction of the Japan Aerospace Exploration Agency's Kibo laboratory. The shuttle and station crews will attach a platform to the outside of the Japanese module. The platform will serve as a type of "front porch" for experiments that require direct exposure to space. Journalists must apply for credentials to attend the liftoff from NASA's Kennedy Space Center in Florida or cover the mission from other NASA centers. To be accredited, reporters must work for verifiable news-gathering organizations. Journalists may need to submit requests for credentials at multiple NASA facilities as early as May 15. Additional time may be required to process accreditation requests by journalists from certain designated countries. Designated countries include those with which the United States has no diplomatic relations, countries on the State Department's list of state sponsors of terrorism, those under U.S. sanction or embargo, and countries associated with proliferation concerns. Please contact the accrediting NASA center for details. Journalists should confirm they have been accredited before they travel. No substitutions of credentials are allowed at any NASA facility. If the STS-127 launch is delayed, the deadline for domestic journalists may be extended on a day-by-day basis. KENNEDY SPACE CENTERReporters applying for credentials at Kennedy should submit requests via the Web at: https://media.ksc.nasa.gov Reporters must use work e-mail addresses, not personal accounts, when applying. After accreditation is approved, applicants will receive confirmation via e-mail. Accredited media representatives with mission badges will have access to Kennedy from launch through the end of the mission. Application deadlines for mission badges are May 24 for foreign reporters and June 4 for U.S. journalists. Access requests must be submitted for Endeavour's move from Launch Pad 39B to pad 39A targeted, which is targeted for May 29, and the launch dress rehearsal activities known as the Terminal Countdown Demonstration Test, which is scheduled for May 31-June 2. Foreign journalists must apply by May 15 to allow time for processing, and U.S. media representatives must apply by May 26. Media badges will be valid for both events. Reporters with special logistic requests for NASA's Kennedy Space Center, such as space for satellite trucks, trailers, electrical connections or work space, must contact Laurel Lichtenberger at laurel.a.lichtenberger@nasa.gov by May 26. The free wireless Internet access provided at Kennedy's news center is no longer available. Work space in the news center and the news center annex is provided on a first-come basis, limited to one space per organization. To set up temporary telephone, fax, ISDN or network lines, media representatives must make arrangements with BellSouth at 800-213-4988. Reporters must have an assigned seat in the Kennedy newsroom prior to setting up lines. To obtain an assigned seat, contact Patricia Christian at patricia.christian-1@nasa.gov. Journalists must have a public affairs escort to all other areas of Kennedy except the Launch Complex 39 cafeteria. JOHNSON SPACE CENTERReporters may obtain credentials for NASA's Johnson Space Center in Houston by calling the Johnson newsroom at 281-483-5111 or by presenting STS-127 mission credentials from Kennedy. Media representatives planning to cover the mission only from Johnson need to apply for credentials only at Johnson. Deadlines for submitting Johnson accreditation requests are May 15 for non-U.S. reporters, regardless of citizenship, and June 5 for U.S. reporters who are U.S. citizens. Journalists covering the mission from Johnson using Kennedy credentials also must contact the Johnson newsroom by June 5 to arrange workspace, phone lines and other logistics. Johnson is responsible for credentialing media if the shuttle lands at NASA's White Sands Space Harbor, N.M. If a landing is imminent at White Sands, Johnson will arrange credentials. DRYDEN FLIGHT RESEARCH CENTERNotice for a space shuttle landing at NASA's Dryden Flight Research Center on Edwards Air Force Base in California could be short. Domestic media outlets should consider accrediting Los Angeles-based personnel who could travel quickly to Dryden. Deadlines for submitting Dryden accreditation requests are May 22 for non-U.S. media, regardless of citizenship, and June 22 for U.S. media who are U.S. citizens or who have permanent residency status. For Dryden media credentials, U.S. citizens representing domestic media outlets must provide their full name, date of birth, place of birth, media organization, their driver's license number and the name of the issuing state, and the last six digits of their social security number. In addition to the above requirements, foreign media representatives, regardless of citizenship, must provide data including their citizenship, visa or passport number and its expiration date. Foreign nationals representing either domestic or foreign media who have permanent residency status must provide their alien registration number and expiration date. Journalists should fax requests for credentials on company letterhead to 661-276-3566. E-mailed requests to Alan Brown at alan.brown@nasa.gov are acceptable for reporters who have been accredited at Dryden within the past year. Requests must include a phone number and business e-mail address for follow-up contact. Those journalists who previously requested credentials will not have to do so again. NASA PUBLIC AFFAIRS CONTACTS:Kennedy Space Center: Candrea Thomas, 321-867-2468, candrea.k.thomas@nasa.gov Johnson Space Center: James Hartsfield, 281-483-5111, james.a.hartsfield@nasa.gov Dryden Flight Research Center: Leslie Williams, 661-276-3893, leslie.a.williams@nasa.govFor information about the STS-127 mission, visit: http://www.nasa.gov/shuttle
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NASA is preparing to fly a small satellite about the size of a loaf of bread that could help scientists better understand how effectively drugs work in space. The nanosatellite, known as PharmaSat, is a secondary payload aboard a U.S. Air Force four-stage Minotaur 1 rocket planned for launch the evening of May 5. PharmaSat weighs approximately 10 pounds. It contains a controlled environment micro-laboratory packed with sensors and optical systems that can detect the growth, density and health of yeast cells and transmit that data to scientists for analysis on Earth. PharmaSat also will monitor the levels of pressure, temperature and acceleration the yeast and the satellite experience while circling Earth at 17,000 miles per hour. Scientists will study how the yeast responds during and after an antifungal treatment is administered at three distinct dosage levels to learn more about drug action in space, the satellite's primary goal. The Minotaur 1 rocket is on the launch pad at NASA's Wallops Flight Facility and the Mid-Atlantic Regional Spaceport located at Wallops Island, Va. The Wallops range is conducting final checkouts. The U.S. Air Force has announced that the rocket could launch at any time during a three-hour launch window beginning at 8 p.m. EDT May 5. "Secondary payload nanosatellites expand the number of opportunities available to conduct research in microgravity by providing an alternative to the International Space Station or space shuttle conducted investigations," said Elwood Agasid , PharmaSat project manager at NASA's Ames Research Center in Moffett Field, Calif. "The PharmaSat spacecraft builds upon the GeneSat-1 legacy with enhanced monitoring and measurement capabilities, which will enable more extensive scientific investigation." After PharmaSat separates from the Minotaur 1 rocket and successfully enters low Earth orbit at approximately 285 miles above Earth, it will activate and begin transmitting radio signals to two ground control stations. The primary ground station at SRI International in Menlo Park, Calif., will transmit mission data from the satellite to the spacecraft operators in the mission control center at NASA's Ames Research Center. A secondary station is located at Santa Clara University in Santa Clara, Calif. When NASA spaceflight engineers make contact with PharmaSat, which could happen as soon as one hour after launch, the satellite will receive a command to initiate its experiment, which will last 96 hours. Once the experiment begins, PharmaSat will relay data in near real-time to mission managers, engineers and project scientists for further analysis. The nanosatellite could transmit data for as long as six months. " PharmaSat is an important experiment that will yield new information about the susceptibility of microbes to antibiotics in the space environment," said David Niesel, and David Niesel PharmaSat's co-investigator from the University of Texas Medical Branch Department of Pathology and Microbiology and Immunology in Galveston. "It also will prove that biological experiments can be conducted on sophisticated autonomous nanosatellites." As with NASA's previous small satellite missions, such as the GeneSat-1, which launched in 2006 and continues to transmit a beacon to Earth, Santa Clara University invites amateur radio operators around the world to tune in to the satellite's broadcast. For more information and instructions about how to contact PharmaSat, visit: http://www.nasa.gov/mission_pages/smallsats/pharmasat.html
To view the launch via webcast, visit:
http://sites.wff.nasa.gov/webcast
For the more information about PharmaSat and other small satellite missions, visit:
http://www.nasa.gov/mission_pages/smallsats
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 NASA's Mars Exploration Rover Spirit drove on Thursday for the first time since April 8, acting on commands from engineers who are still investigating bouts of amnesia and other unusual behavior exhibited by Spirit in the past two weeks. The drive took Spirit about 1.7 meters (5.6 feet) toward destinations about 150 meters (about 500 feet) away. The rover has already operated more than 20 times longer than its original prime mission on Mars. This week, rover engineers at NASA's Jet Propulsion Laboratory, Pasadena, Calif., judged that it would be safe to send Spirit commands for Thursday's drive. They also anticipated that, if the rover did have another amnesia event, the day's outcome could be helpful in diagnosing those events. Three times in the past two weeks, Spirit has failed to record data from a day's activity period into non-volatile flash memory. That is a type of computer memory where information is preserved even when power is off, such as when the rover naps to conserve power. "We expect we will see more of the amnesia events, and we want to learn more about them when we do," said JPL's Sharon Laubach, chief of the rover sequencing team, which develops and checks each day's set of commands. The team is also investigating two other types of problems Spirit has experienced recently: failing to wake up for three consecutive communication sessions about two weeks ago and rebooting its computer on April 11, 12 and 18. Engineers have not found any causal links among these three types of events. After checking last week whether moving the rover's high-gain antenna could trigger problems, routine communication via that dish antenna resumed Monday. Spirit has maintained stable power and thermal conditions throughout the problem events this month, although power output by its solar panels has been significantly reduced since mid-2007 by dust covering the panels. "We decided not to wait until finishing the investigations before trying to drive again," Laubach said. "Given Spirit's limited power and the desire to make progress toward destinations to the south, there would be risks associated with not driving." The team has made a change in Spirit's daily routine in order to aid the diagnostic work if the rover experiences another failure to record data into flash memory. To conserve energy, Spirit's daily schedule since 2004 has typically included a nap between the rover's main activities for the day and the day's main downlink transmission of data to Earth. Data stored only in the rover's random-access memory (RAM), instead of in flash memory, is lost during the nap, so when Spirit has a flash amnesia event on that schedule, the team gets no data from the activity period. The new schedule puts the nap before the activity period. This way, even if there is a flash amnesia event, data from the activity period would likely be available from RAM during the downlink. Spirit and its twin, Opportunity, completed their original three-month prime missions on Mars in April 2004 and have continued their scientific investigations on opposite sides of the planet through multiple mission extensions. Engineers have found ways to cope with various symptoms of aging on both rovers. This week, Opportunity completed drives of 96 meters (315 feet) Tuesday, 137 meters (449 feet) Wednesday and 95 meters (312 feet) Thursday in its long-term trek toward a crater more than 20 times larger than the biggest it has visited so far. JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA's Science Mission Directorate, Washington.
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 If you're reading this at the end of the day on Sunday, April 26th—stop! You're supposed to be outside looking at the sunset. On Sunday evening, the crescent Moon, Mercury and the Pleiades star cluster will gather for a three-way conjunction in the western sky. It's a must-see event. The show begins before the sky fades to black. The Moon pops out of the twilight first, an exquisitely slender 5% crescent surrounded by cobalt blue. The horns of the crescent cradle a softly-glowing image of the full Moon. That is Earthshine—dark lunar terrain illuminated by sunlight reflected from Earth. If the show ended then and there, you'd be satisfied. But there's more. Shortly after the Moon appears, Mercury materializes just below it. The innermost planet has emerged from the glare of the sun for its best apparition of the year in late April—perfect timing for a sunset encounter with the Moon. To the naked eye, Mercury looks like a pink 1st-magnitude star. The planet itself is not pink; it only looks that way because it has to shine through dusty lower layers of Earth’s atmosphere. A backyard telescope pointed at Mercury reveals a tiny fat crescent. The innermost planet has phases like the Moon! Next, do nothing. Spend some quiet moments absorbing the view. As the twilight deepens, your eyes will dark-adapt and—voilà! There are the Pleiades.  Also known as the Seven Sisters, the Pleiades are a cluster of young stars about a hundred light years from Earth. They form a miniature Little Dipper located, on this particular evening, halfway between Mercury and the Moon. The brightest stars of the cluster are only 2nd magnitude, not terrifically bright. Nevertheless, the Pleiades are compelling in disproportion to their luminosity. Every ancient culture--Greek, Maya, Aztec, Aborigine, Māori and others—put the cluster in its myths and legends. On April 26th you may discover why, even if you cannot articulate your findings. The Pleiades, Moon and Mercury are all visible to the naked eye even from light-polluted cities. Nevertheless, if you have binoculars, use them. A quick scan of the threesome reveals a rugged moonscape in startling detail, the rich pink hue of Mercury, and many more than seven sisters (there are hundreds of stars in the cluster).
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 Imagine a monster tornado is ripping through a neighboring county and bearing down on yours. If you live in north Alabama, your forecasters are well prepared to tell you when to seek shelter. The National Weather Service there shares a building – the National Space Science and Technology Center – with NASA's Short-term Prediction Research and Transition, or SPoRT, Center. SPoRT puts state-of-the-art NASA satellite data directly into forecasters hands, arming them to recognize weather that threatens your safety. "It's not just a matter of them throwing random data sets over the fence to us and hoping we might be able to use them," says Chris Darden from the National Weather Service (NWS). "They work with us to figure out precisely what we need. Then they put that data into a format we can read, actually integrating it with our radar displays. And they train us to understand and interpret the information they give us." Dr. Gary Jedlovec, SPoRT principal investigator, notes, "We're all in this together in this building, and the public is the ultimate winner. Adding our data to NWS weather models helps forecasters give the community accurate advanced warnings." That tornado plowing through an adjoining county is a prime example. SPoRT gives forecasters several tools to help predict a thunderstorm’s potential for spawning such a beast. One of the best such tools is the North Alabama Lightning Mapping Array -- an 11-sensor network that measures lightning around the area. Think of how your radio crackles noisily when lightning flashes. That's because lightning produces a lot of radio frequency noise. By zeroing in on an unused frequency, the 11 sensors scattered around on water towers, radio towers, and roof tops, measure a storm's total amount of lightning. "The total lightning data can help forecasters predict whether a storm might generate a tornado," says Rich Blakeslee, NASA atmospheric scientist. "We've found that often intercloud lightning – not cloud-to-ground lightning -- suddenly spikes and then, just as suddenly, diminishes a very few minutes before a tornado forms." Darden adds, "We add the total real-time lightning data to our radar and wind velocity information to help us make that critical decision whether to send out a warning." SPoRT and other NSSTC programs also have access to another tool -- a Dual-Polarimetric Doppler Radar -- that actually reveals the shapes of raindrops. Traditional weather radar sends pulses of radiation that oscillate in one direction only--horizontally. Dual polarization radar sends pulses that oscillate in two directions--horizontally and vertically. By combining the reflections from both kinds of pulses, scientists can tell what shape and size a raindrop is. "Flatter and wider means bigger raindrops, because the larger the raindrop is the flatter it gets as it falls," explains Walt Petersen, NASA physical scientist. "That information helps weather forecasters better estimate rainfall amounts – and therefore flash flooding – and storm intensity." This radar can also tell the difference between rain and hail because hail is typically spherical while raindrops tend to flatten. Adding this information to the strength of the return, forecasters can tell the size of the hail. "Large hail indicates powerful updraft and downdraft winds within a thunderstorm," says Petersen. "So it usually means a strong storm, and sometimes means that a storm may produce a tornado." "This radar tells us a lot about a potentially violent storm," says Darden. "It's pretty new, so we still have a lot to learn." No problem. The scientists at the NSSTC train current forecasters and future meteorologists alike to use these cutting-edge tools. University of Alabama Huntsville's Atmospheric Science Department is, like the NWS, collocated with NASA researchers at NSSTC. "During severe weather, day or night, my students gather here to operate the radar," says Petersen. "You should see 'em. It's like weather central here sometimes! "When there's a fierce storm brewing, or even crashing around us, the students, UAH and NASA researchers, and forecasters communicate in real time by instant messaging with the NWS's IEM online chat tool ( NWSChat). They chat about operating the radar and interpreting the radar data. It's a great hands-on way to learn." "So the benefit goes straight to the consumer--the viewing audience," says Petersen. And the benefits are not just local. "We've transferred many of these tools to other forecast offices across the country," says Darden. "For example, our office is one of only a few U.S. NWS offices with access to this kind of radar, but all the offices must convert their radars to dual pole by the end of next year. We'll be helping to train them in its use, passing along what we've learned from SPoRT." Both the lightning mapping and dual pole radar are ground-based now, but in the future will be space-based. "We're developing products to work with the Geostationary Lightning Mapper on GOES-R – NOAA's next-generation weather satellite," says Jedlovec. "With the launch of that satellite in about 2015, lightning could be mapped all across the U.S. from the vantage point of space." Again, thanks to NASA, the NWS forecasters here will be a step ahead in using a new tool, and ready to help other forecasters learn the ropes to help their communities. "This is an exciting place to work," says Jedlovec. "All the tornado warnings for Madison County come right out of this building. We don't just write research papers. With the help of the National Weather Service, we see our data used for the good of the public. That makes us feel good about what we do."
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 An international team of astronomers has used the world’s biggest radio telescope to look deep into the brightest galaxies that NASA’s Fermi Gamma-ray Space Telescope can see. The study solidifies the link between an active galaxy’s gamma-ray emissions and its powerful radio-emitting jets. “Now we know for sure that the fastest, most compact, and brightest jets we see with radio telescopes are the ones that are able to kick light up to the highest energies,” said Yuri Kovalev, a team member at the Max Planck Institute for Radio Astronomy in Bonn, Germany. The brightest galaxies Fermi sees are active galaxies, which emit oppositely directed jets of particles traveling near the speed of light. Some, called blazars, are especially bright because one of the jets happens to be directed toward us. Astronomers believe that these jets somehow arise as a consequence of matter falling into a massive black hole at the galaxy’s center, but the process is not well understood.  To peer into the jets, Kovalev and his colleagues used the National Science Foundation’s Very Long Baseline Array ( VLBA), a set of ten radio telescopes located from Hawaii to St. Croix in the U.S. Virgin Islands and operated by the National Radio Astronomy Observatory. When the signals from these telescopes are combined, the array acts like a single enormous radio dish more than 5,300 miles across. The VLBA can resolve details about a million times smaller than Fermi can and 50 times smaller than any optical telescope. The new findings are an outcome of the MOJAVE program, a long-term study of the jets from active galaxies using the VLBA. “We see the innermost few hundred light-years of these jets for even the most distant active galaxies seen by Fermi,” Kovalev noted. For decades, astronomers have wondered about the nature of these radio-emitting jets. Hints that they also emit radiation at higher energies came from NASA’s Compton Gamma-Ray Observatory, which operated throughout the 1990s, and, more recently, from observations by NASA’s Chandra X-Ray Observatory. Fermi’s Large Area Telescope (LAT) scans the entire sky every three hours. These quick snapshots of the gamma-ray sky allow astronomers to better monitor sudden flares from active galaxies. The astronomers combined VLBA data of active galaxies with Fermi observations. Active galaxies detected in the LAT’s first few months of operations generally possess brighter and more compact radio jets than galaxies the LAT did not see. Moreover, an active galaxy’s radio jets tend to be brighter in the months following any gamma-ray flares observed by the LAT.Kovalev and his colleagues also see a correlation between active galaxies with the brightest gamma-ray emission and those with the fastest jets. Because we see these jets nearly end on, and because the particles within the jets move close to the speed of light, the VLBA can study a phenomenon called “ Doppler boosting.” This makes radio-emitting blobs look brighter and appear to move much faster that the speed of light.  The VLBA data show that the bigger the Doppler boost seen in a radio jet, the more likely it is that Fermi recorded it as a variable gamma-ray source. In addition, many objects found by Fermi to be extreme in gamma-rays are broadcasting strong bursts of radio emission at about the same time. All this points to the team’s conclusion that the portion of an active galaxy’s radio jet closest to the galaxy’s core is also the source of the gamma-rays Fermi detects. The team’s findings appear in two papers to be published in the May 1 issue of The Astrophysical Journal Letters. “For more than a decade, we have collected images of the brightest galaxies in the radio sky to study the changing structures of their jets,” said Matthew Lister, a professor at Purdue University and a member of the research team. Lister leads the MOJAVE program and is also a Fermi guest investigator. "We've waited a long time to compare our measurements with the findings in the gamma-ray sky -- and now, thanks to this state-of-the-art space observatory, we finally can." Related Links:> MOJAVE team press release > Fermi's Best-Ever Look at the Gamma-Ray Sky> NASA's Fermi Mission, Namibia's HESS Telescopes Explore a Blazar > More MOJAVE images of radio galaxies
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 NASA, the United States National Arboretum and American Forests teamed up Wednesday to celebrate Earth Day 2009 by planting a historic Moon Sycamore on the arboretum's grounds in Washington. During the Apollo 14 moon mission in 1971, NASA astronaut Stuart Roosa, a former U.S. Forest Service smoke jumper, took with him tree seeds from a Loblolly Pine, Sycamore, Sweet Gum, Redwood, and Douglas Fir. After Roosa's return to Earth, the original seeds were germinated by the U.S. Forest Service and the result was "moon trees." Moon trees now grow at state capitols and university campuses across the nation. A Moon Sycamore also shades Roosa's grave at Arlington National Cemetery. "Astronauts have described the view of Earth as a grand oasis in the vastness of space," said Alan Ladwig, a senior advisor to the NASA administrator. "Since any good oasis comes with lots of greenery, it is fitting that today we plant this Sycamore, which is a legacy tree grown from descendant seeds of Stuart Roosa's original Apollo experiment. It is a solid reminder that space exploration and life here on Earth are inextricably tied." Ladwig, who represented NASA at the ceremony, also recalled the words of Apollo 8 astronaut Bill Anders after he snapped the historic Earthrise photo on December 1968: "We came all this way to explore the moon and the most important thing is that we discovered the Earth. NASA continues to study Earth from the unique vantage point of space with 15 Earth observing satellites now in orbit. Another 11 Earth missions are in development or under study.  American Forests, the nation’s oldest conservation organization, continues the legacy of this unique Apollo-era tree program by maintaining second generation moon trees and making them available for sale to the public through their Historic Trees Program. "Like space exploration, trees can also capture one’s imagination," said Deborah Gangloff, executive director of American Forests. "To plant a tree grown from one set out by George Washington or appreciated by Frederick Douglass or from a seed taken to the moon, connects us with important people and events in history. By planting this Moon tree today, we hope to inspire a new generation to imagine the stars while protecting our life-giving environment." American Forests’ mission is to grow a healthier world by working with communities on local efforts that restore and maintain forest ecosystems. Its work encompasses planting trees, calculating the value of urban forests, fostering environmental education, and improving public policy for trees at the national level. The organization has a goal of having100 million trees planted by 2020. For additional information about the Moon Trees, visit: http://www.nasa.gov/externalflash/moonTrees/index.htmlTo get information about NASA's 40th Apollo anniversary, visit: www.nasa.gov/apollo40thFor more information about NASA and Earth Day, visit: http://www.nasa.gov/earthdayFor more information on American Forests, visit www.americanforests.org
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 The burning of trees and plants in the savannas of southern Africa creates massive aerosol plumes that drift high above the land mass. The aerosols – tiny suspended particles created by the fires – present an unruly variable for climate science. Some aerosols reflect incoming solar radiation and create cooling; some trap heat and warm the atmosphere. A lack of high accuracy data has restricted scientists' ability to better quantify how much aerosols contribute to global warming or cooling. New research, using measurements from one of NASA's fifteen operating research satellites, shows that the warming effect of aerosols increases with the amount of cloud cover below the aerosols, according to a paper published recently in Nature Geoscience by a team of scientists from the United States and India. In fact, the relationship between aerosol warming/cooling and strength of cloud cover was found to be nearly linear, making it possible for researchers to define the critical amount of cloud cover at which aerosols switch from producing a cooling to a warming effect. That newfound capability could improve long-term projections of global climate models that pull together many processes about the changing planet. Incorporating new understanding of the atmosphere, such as the relationship between clouds and aerosols, will improve climate projections that policymakers use to design the best responses to global climate change. Using the vertical profiles of cloud and aerosol layers produced by NASA's Cloud Aerosol Lidar and Infrared Pathfinder Satellite Observation ( CALIPSO) mission, the researchers, led by Duli Chand, looked at a region of the southeastern Atlantic Ocean during July-October of 2006 and 2007. This region was chosen because climate models often disagree about the net effect of aerosols produced by frequent fires in southern Africa. They found that smoke from fires create more warming in the atmosphere when there is a layer of clouds underneath the aerosols. The estimated amount of warming can increase by three times when the vertical patterns of clouds and aerosols are taken into account. "What motivated us was we knew this was an area where the global models disagree strongly," said Rob Wood, a professor of atmospheric sciences at the University of Washington. "We knew CALIPSO could see these aerosols above these clouds in ways other instruments couldn't." As Woods' findings showed, that ability to see multiple layers of the atmosphere led directly to more accurate measurements. David Winker, CALIPSO's principal investigator at NASA's Langley Research Center, said the findings of the research team bring into sharper focus the aerosol-cloud relationship. "Their result is fairly significant," Winker said. "It showed something we've thought about for quite awhile but have been unable to quantify. It's an example of the kind of unique contribution that CALIPSO can make to our understanding of climate change." Winker said climate change models could benefit from this kind of information. He and others are working on creating data sets that could be used to improve the aerosol-cloud relationship in these models. "We're working toward data sets that could do that. By the time we have those data sets ready, the general circulation models will probably be able to use them," Winker said. Wood said he was surprised to find such a strong relationship between cloud cover and aerosols' impact on warming or cooling. He said defining the switching point between warming and cooling seemed particularly sensitive to the single-scattering albedo – which determines how, for instance, a dust or soot particle scatters or absorbs radiation -- of aerosols. Wood said he and others who worked on the paper are interested in trying to incorporate their findings into large-scale climate models. "Ideally, we'd like to get some collaboration going and look at the models and look at our data," he said.
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NASA scientists have proposed an ingenious and remarkably resourceful process to produce " clean energy" biofuels, while it cleans waste water, removes carbon dioxide from the air, retains important nutrients, and does not compete with agriculture for land or freshwater. When astronauts go into space, they must bring everything they need to survive. Living quarters on a spaceship require careful planning and management of limited resources, which is what inspired the project called “ Sustainable Energy for Spaceship Earth.” It is a process that produces " clean energy" biofuels very efficiently and very resourcefully.  "The reason why algae are so interesting is because some of them produce lots of oil," said Jonathan Trent, the lead research scientist on the Spaceship Earth project at NASA Ames Research Center, Moffett Field, Calif. “In fact, most of the oil we are now getting out of the ground comes from algae that lived millions of years ago. Algae are still the best source of oil we know." Algae are similar to other plants in that they remove carbon dioxide from the atmosphere, produce oxygen as a by-product of photosynthesis, and use phosphates, nitrogen, and trace elements to grow and flourish. Unlike many plants, they produce fatty, lipid cells loaded with oil that can be used as fuel. Land plants currently used to produce biodiesel and other fuels include soy, canola, and palm trees. For the sake of comparison, soy beans produce about 50 gallons of oil per acre per year; canola produces about 160 gallons per acre per year, and palms about 600 gallons per acre per year. But some types of algae can produce at least 2,000 gallons of oil per acre per year. The basic problem is growing enough algae to meet our country's enormous energy-consumption demands. Although algae live in water, land-based methods are used to grow algae. Two land-based methods used today are open ponds and closed bioreactors. Open ponds are shallow channels filled with freshwater or seawater, depending on the kind of algae that is grown. The water is circulated with paddle wheels to keep the algae suspended and the pond aerated. They are inexpensive to build and work well to grow algae, but have the inevitable problem of water evaporation. To prevent the ponds from drying out or becoming too salty, conditions that kill the algae, an endless supply of freshwater is needed to replenish the evaporating water. When closed bioreactors are used to grow algae, water evaporation is no longer the biggest problem for algae's mass-production. Bioreactors, enclosed hardware systems made of clear plastic or glass, present their own problems. They can be computer-controlled and monitored around the clock for a more bountiful supply of algae. However, storing water on land and controlling its temperature are the big problems, making them prohibitively expensive to build and operate. In addition, both systems require a lot of land. "The inspiration I had was to use offshore membrane enclosures to grow algae. We're going to deploy a large plastic bag in the ocean, and fill it with sewage. The algae use sewage to grow, and in the process of growing they clean up the sewage," said Trent. It is a simple, but elegant concept. The bag will be made of semi-permeable membranes that allow fresh water to flow out into the ocean, while retaining the algae and nutrients. The membranes are called “forward-osmosis membranes.” NASA is testing these membranes for recycling dirty water on future long-duration space missions. They are normal membranes that allow the water to run one way. With salt water on the outside and fresh water on the inside, the membrane prevents the salt from diluting the fresh water. It’s a natural process, where large amounts of fresh water flow into the sea. Floating on the ocean's surface, the inexpensive plastic bags will be collecting solar energy as the algae inside produce oxygen by photosynthesis. The algae will feed on the nutrients in the sewage, growing rich, fatty cells. Through osmosis, the bag will absorb carbon dioxide from the air, and release oxygen and fresh water. The temperature will be controlled by the heat capacity of the ocean, and the ocean's waves will keep the system mixed and active. When the process is completed, biofuels will be made and sewage will be processed. For the first time, harmful sewage will no longer be dumped into the ocean. The algae and nutrients will be contained and collected in a bag. Not only will oil be produced, but nutrients will no longer be lost to the sea. According to Trent, the system ideally is fail proof. Even if the bag leaks, it won’t contaminate the local environment. The enclosed fresh water algae will die in the ocean. The bags are expected to last two years, and will be recycled afterwards. The plastic material may be used as plastic mulch, or possibly as a solid amendment in fields to retain moisture. “We have to remember,” Trent said, quoting Marshall McLuhan: “ we are not passengers on spaceship Earth, we are the crew.” For further information, please visit: http://www.nasa.gov/centers/ames/greenspace/Or visit: http://www.nasa.gov/ames
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 Tired of those boring old tracking maps that show the space station going around and around the Earth, and wondering what the view from up there must be like? Well, what better way to celebrate Earth Day than by taking a look at the Earth below from where the International Space Station is right now? Thanks to the wonders of the World Wide Web (the Internet, that is), real-time tracking data beamed down from the space station and the fabulous catalog of NASA handheld orbital photography -- the Gateway to Astronaut Photography of Earth -- you can do just that! Here’s how it works: just go to http://external.jsc.nasa.gov/events/issphotos/.NASA’s web site will check the telemetry from the space station and gather its exact latitude and longitude as it orbits about 200 miles over the Earth, traveling 17,500 miles an hour, making one full orbit every hour and a half. Using that information, the web site will check the extensive collection of images that have been taken from as far back as the Gemini Program, and return to you images of rivers, lakes, mountains, cities, railroads, ports, volcanoes, deserts and islands below. Since the Earth’s surface is three-quarters water, the web site will draw a virtual “ box” around the latitude and longitude found, and expand that box if necessary to find some photos of land masses or islands that are nearby. Though taken at different times and under different sunlight than the current time, the images display the many facets of the Earth. While this isn’t exactly giving you an opportunity to remotely snap a picture from the space station, it’s the next best thing – and you’ll rarely get a picture of a cloudy day below! For more information about the International Space Station, which is celebrating its 10th anniversary on orbit this year, visit: http://www.nasa.gov/stationFor more information about the imagery and the Crew Earth Observations group at NASA’s Johnson Space Center in Houston, Texas, visit: http://eol.jsc.nasa.gov/
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 Mars Exploration Rover Mission Status Report After three days of completing Earth-commanded activities without incident last week, NASA's Mars Exploration Rover Spirit had a bout of temporary amnesia Friday, April 17, and rebooted its computer Saturday, April 18, behavior similar to events about a week earlier. Engineers operating Spirit are investigating the reboots and the possibly unrelated amnesia events, in which Spirit unexpectedly fails to record data into the type of memory, called flash, where information is preserved even when power is off. Spirit has had three of these amnesia events in the past 10 days, plus one on Jan. 25. No causal link has been determined between the amnesia events and the reboots. The most recent reboot put Spirit back into an autonomous operations mode in which the rover keeps itself healthy. Spirit experienced no problems in this autonomous mode on Sunday. The rover team at NASA's Jet Propulsion Laboratory, Pasadena, Calif., revised plans today for regaining Earth control of Spirit's operations and resuming diagnostic and recovery activities by the rover. "We are proceeding cautiously, but we are encouraged by knowing that Spirit is stable in terms of power and thermal conditions and has been responding to all communication sessions for more than a week now," said JPL's Sharon Laubach, chief of the rover sequencing team, which develops and checks each day's set of commands. During the past week of diagnostic activities, the rover has successfully moved its high-gain dish antenna and its camera mast, part of checking whether any mechanical issues with those components may be related to the reboots, the amnesia events, or the failure to wake up for three consecutive communication sessions two weeks ago. Spirit and its twin rover, Opportunity, completed their original three-month prime missions on Mars in April 2004 and have continued their scientific investigations on opposite sides of the planet through multiple mission extensions. Engineers have found ways to cope with various symptoms of aging on both rovers. The current diagnostic efforts with Spirit are aimed at either recovering undiminished use of the rover or, if some capabilities have been diminished, to determine the best way to keep using the rover. Sharon Laubach said, "For example, if we do determine that we can no longer use the flash memory reliably, we could design operations around using the random-access memory." Spirit has 128 megabytes of random-access memory, or RAM, which can store data as long as the rover is kept awake before its next downlink communications session. JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA's Science Mission Directorate, Washington.
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 To commemorate the Hubble Space Telescope's 19 years of historic, trailblazing science, the orbiting telescope has photographed a peculiar system of galaxies known as Arp 194. This interacting group contains several galaxies, along with a " cosmic fountain" of stars, gas, and dust that stretches over 100,000 light-years. The northern (upper) component of Arp 194 appears as a haphazard collection of dusty spiral arms, bright blue star-forming regions, and at least two galaxy nuclei that appear to be connected and in the early stages of merging. A third, relatively normal, spiral galaxy appears off to the right. The southern (lower) component of the galaxy group contains a single large spiral galaxy with its own blue star-forming regions. However, the most striking feature of this galaxy troupe is the impressive blue stream of material extending from the northern component. This " fountain" contains complexes of super star clusters, each one of which may contain dozens of individual young star clusters. The blue color is produced by the hot, massive stars which dominate the light in each cluster. Overall, the " fountain" contains many millions of stars. These young star clusters probably formed as a result of the interactions between the galaxies in the northern component of Arp 194. The compression of gas involved in galaxy interactions can enhance the star-formation rate and give rise to brilliant bursts of star formation in merging systems. Hubble's resolution shows clearly that the stream of material lies in front of the southern component of Arp 194, as evidenced by the dust that is silhouetted around the star-cluster complexes. It is therefore not entirely clear whether the southern component actually interacts with the northern pair. The details of the interactions among the multiple galaxies that make up Arp 194 are complex. The shapes of all the galaxies involved appear to have been distorted, possibly by their gravitational interactions with one another. Arp 194, located in the constellation Cepheus, resides approximately 600 million light-years away from Earth. It contains some of the many interacting and merging galaxies known in our relatively nearby universe. These observations were taken in January of 2009 with the Wide Field Planetary Camera 2. Images taken through blue, green, and red filters were combined to form this picturesque image of galaxy interaction.
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Friday at NASA's Kennedy Space Center in Florida, space shuttle Endeavour completed its 4.2-mile trek from the Vehicle Assembly Building to Launch Pad 39B. With Atlantis on nearby Launch Pad 39A, this marks the final time that two shuttles will be on the launch pads at the same time, as the shuttle program draws to a close next year. Atlantis is targeted for liftoff May 12 at 1:31 p.m. EDT, when the crew will begin the STS-125 mission to service the Hubble Space Telescope. Atlantis' mission payload is set to arrive at the launch pad Saturday evening. Prior to its STS-127 mission to the International Space Station, Endeavour will remain on standby at the launch pad in the unlikely event that a rescue mission for the Atlantis crew members would be necessary during their mission. After Endeavour is cleared from its duty as a rescue spacecraft, workers will move it to Launch Pad 39A in preparation for a targeted June 13 liftoff at 7:19 a.m. EDT. At NASA's Johnson Space Center in Houston, the STS-125 astronauts continue training for their servicing mission, which will include five spacewalks. Space Shuttles Endeavour and Atlantis at Launch Pads STS-125: Mission to Service NASA's Hubble Space TelescopeVeteran astronaut Scott Altman will command the final space shuttle mission to service NASA's Hubble Space Telescope, and retired Navy Capt. Gregory C. Johnson will serve as pilot. Mission specialists rounding out the crew are: veteran spacewalkers John Grunsfeld and Mike Massimino, and first-time space fliers Andrew Feustel, Michael Good and Megan McArthur. During the 11-day mission's five spacewalks, astronauts will install two new instruments, repair two inactive ones and perform the component replacements that will keep the telescope functioning into at least 2014. In addition to the originally scheduled work, Atlantis also will carry a replacement Science Instrument Command and Data Handling Unit for Hubble. Astronauts will install the unit on the telescope, removing the one that stopped working on Sept. 27, 2008, delaying the servicing mission until the replacement was ready.
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NASA centers across the nation invite journalists and the public to see and hear about the agency's efforts and contributions to understanding and protecting Earth. Begun in 1970, Earth Day is the annual celebration of the environment and a time to assess work still needed to protect the natural resources of our planet. The agency maintains the largest contingent of dedicated Earth scientists and engineers in leading and assisting other agencies in preserving the planet's environment. For a comprehensive listing of NASA Earth Day activities, visit: http://www.nasa.gov/earthday The Web site also features an online poll inviting the public to vote for the most important contribution NASA has made to exploring Earth and improving the way we live on our home planet. The " greatest hits" poll closes April 21. A new interactive feature will debut on Earth Day, April 22, that allows visitors to view a collection of astronaut photographs of Earth as seen from the current location of the International Space Station. Please note all times are local. NASA center events include: NASA Headquarters, Washington Sunday, April 19 (12 - 7 p.m. EDT) - NASA is participating in the Earth Day Celebration at the National Mall with an exhibit on a wide range of environmental issues as seen from space, including air pollution, urban development, hurricanes, and dust storms. Visitors to the booth will be able to meet NASA Earth scientists and see NASA satellite images of Earth. Wednesday, April 22 (1 p.m. EDT) - In honor of Earth Day and the 40th Anniversary of the Apollo program, NASA will take part in an event at the National Arboretum in Washington to plant a moon sycamore tree. The tree was grown from a second-generation seed from seeds flown to the moon and returned to Earth by the crew of Apollo 14 in 1971. Ames Research Center at Moffet Field, Calif. Tuesday, April 21 (9 a.m. - 4 p.m. PDT) - A technology expo sponsored by the NASA Research Park and the NASA Ames Innovative Partnerships Program will showcase technologies related to exploration and sustainability. More than 40 exhibits will be on display underscoring NASA's vision of leveraging technology for a cleaner, greener Earth. Dryden Flight Research Center, Edwards, Calif. Tuesday, April 21 (10 a.m. - 2 p.m. PDT) - View a model of the unmanned Ikhana aircraft. Ikhana was instrumental in assisting emergency response efforts during recent California wildfires. The public also will see high-altitude life-support demonstrations and can attend several educational activities and presentations. Glenn Research Center in Cleveland Sunday, April 19 (10 a.m. - 5 p.m. EDT) - A variety of educational displays will be at the Cleveland Metro Park Zoo. Goddard Space Flight Center in Greenbelt, Md. Wednesday, April 22 (10 a.m. and 2 p.m. EDT) - NASA Goddard Digital Learning Network presents two webcasts for students and teachers of " Bella Gaia" (Beautiful Earth), a unique multimedia journey of Earth from space by director and violinist Kenji Williams. The performance will be broadcast live. For more information, visit http://dln.nasa.gov . Jet Propulsion Laboratory in Pasadena, Calif. Saturday, April 25 and Sunday, April 26 (9 a.m. - 5 p.m. PDT) - JPL will join a celebration of our ocean planet at the ninth annual Earth Day event at the Aquarium of the Pacific in Long Beach, Calif. The event will include exhibits and handouts highlighting NASA's Earth science research. Kennedy Space Center, Fla. Wednesday, April 22 (10 a.m. - 3 p.m. EDT) - Local and county government officials will showcase their environmental activities. Topics will include natural resources, energy conservation, recycling, alternative fuel vehicles and environmentally friendly products. Langley Research Center in Hampton, Va. Saturday, April 18 (1 p.m. EDT) - Presentation on " Looking at Earth from Space" at the Virginia Zoo's "Party for the Planet: Earth Day at the Zoo." Tuesday, April 21 (7 p.m. EDT) - Lecture on "Satellite Observations of Air Pollution: Local Impacts Seen from a Global Perspective" at Thomas Nelson Community College's Espada Conference Center in Hampton. Marshall Space Flight Center in Huntsville, Ala. Tuesday, April 21 (10 a.m. - 12:30 p.m. CDT) - The theme of Marshall's Earth Day event for employees and contractors is water stewardship, with the slogan " Just one drop, priceless." A taste test is planned using water recycled through the Environmental Control and Life Support System used on the International Space Station. A vendor fair will be held highlighting environmentally friendly products. Special guests include local area mayors. Stennis Space Center near Bay St. Louis, Miss. Wednesday, April 22 (10 a.m. - 2 p.m. CDT) - Energy awareness displays and a video presentation highlighting the " green building" aspects of the center's new Emergency Operations Center. Activities also will feature raffles, environmentally focused games, cell phone recycling and other environment-friendly exercises. Wallops Flight Research Facility on Wallops Island, Va. Saturday, April 18 (10 a.m. - 4 p.m. EDT) - Several events will be held in collaboration with the Salisbury Zoo. The theme " Rockets and Critters" focuses on protecting threatened and endangered species while operating a NASA launch range. For information about the NASA and agency activities, visit:
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 The most crowded collision of galaxy clusters has been identified by combining information from three different telescopes. This result gives scientists a chance to learn what happens when some of the largest objects in the Universe go at each other in a cosmic free-for- all. Using data from NASA's Chandra X-ray Observatory, Hubble Space Telescope and the Keck Observatory on Mauna Kea, Hawaii, astronomers were able to determine the three-dimensional geometry and motion in the system MACSJ0717.5+3745 (or MACSJ0717 for short) located about 5.4 billion light years from Earth. The researchers found that four separate galaxy clusters are involved in a triple merger, the first time such a phenomenon has been documented. Galaxy clusters are the largest objects bound by gravity in the Universe. In MACSJ0717, a 13-million-light-year-long stream of galaxies, gas and dark matter – known as a filament - is pouring into a region already full of galaxies. Like a freeway of cars emptying into a full parking lot, this flow of galaxies has caused one collision after another. "In addition to this enormous pileup, MACSJ0717 is also remarkable because of its temperature," said Cheng-Jiun Ma of the University of Hawaii and lead author of the study. "Since each of these collisions releases energy in the form of heat, MACS0717 has one of the highest temperatures ever seen in such a system." While the filament leading into MACJ0717 had been previously discovered, these results show for the first time that it was the source of this galactic pummeling. The evidence is two-fold. First, by comparing the position of the gas and clusters of galaxies, the researchers tracked the direction of clusters’ motions, which matched the orientation of the filament in most cases. Secondly, the largest hot region in MACSJ0717 is where the filament intersects the cluster, suggesting ongoing impacts. " MACSJ0717 shows how giant galaxy clusters interact with their environment on scales of many millions of light years," said team member Harald Ebeling, also from University of Hawaii. "This is a wonderful system for studying how clusters grow as material falls into them along filaments." Computer simulations show that the most massive galaxy clusters should grow in regions where large-scale filaments of intergalactic gas, galaxies, and dark matter intersect, and material falls inward along the filaments. "It's exciting that the data we get from MACSJ0717 appear to beautifully match the scenario depicted in the simulations," said Ma. Multiwavelength data were crucial for this work. The optical data from Hubble and Keck give information about the motion and density of galaxies along the line of sight, but not about their course perpendicular to that direction. By combining the X-ray and optical data, scientists were able to determine the three-dimensional geometry and motion in the system. In the future, Ma and his team hope to use even deeper X-ray data to measure the temperature of gas over the full 13-million-light-year extent of the filament. Much remains to be learned about the properties of hot gas in filaments and whether its infall along these structures can significantly heat the gas in clusters over large scales. "This is the most spectacular and most disturbed cluster I have ever seen,” says Ma, "and we think that we can learn a whole lot more from it about how structure in our Universe grows and evolves." The paper describing these results appeared in the March 10th issue of the Astrophysical Journal Letters. NASA's Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra's science and flight operations from Cambridge, Mass. More information, including images and other multimedia, can be found at: http://chandra.harvard.edu
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NASA's Kepler mission has taken its first images of the star-rich sky where it will soon begin hunting for planets like Earth. The new "first light" images show the mission's target patch of sky, a vast starry field in the Cygnus-Lyra region of our Milky Way galaxy. One image shows millions of stars in Kepler's full field of view, while two others zoom in on portions of the larger region. The images can be seen online at: http://www.nasa.gov/mission_pages/kepler/multimedia/20090416.html "Kepler's first glimpse of the sky is awe-inspiring," said Lia LaPiana, Kepler's program executive at NASA Headquarters in Washington. "To be able to see millions of stars in a single snapshot is simply breathtaking." One new image from Kepler shows its entire field of view -- a 100-square-degree portion of the sky, equivalent to two side-by-side dips of the Big Dipper. The regions contain an estimated 14 millions stars, more than 100,000 of which were selected as ideal candidates for planet hunting. Two other views focus on just one-thousandth of the full field of view. In one image, a cluster of stars located about 13,000 light-years from Earth, called NGC 6791, can be seen in the lower left corner. The other image zooms in on a region containing a star, called Tres-2, with a known Jupiter-like planet orbiting every 2.5 days. "It's thrilling to see this treasure trove of stars," said William Borucki, science principal investigator for Kepler at NASA's Ames Research Center at Moffett Field, Calif. "We expect to find hundreds of planets circling those stars, and for the first time, we can look for Earth-size planets in the habitable zones around other stars like the sun." Kepler will spend the next three-and-a-half years searching more than 100,000 pre-selected stars for signs of planets. It is expected to find a variety of worlds, from large, gaseous ones, to rocky ones as small as Earth. The mission is the first with the ability to find planets like ours -- small, rocky planets orbiting sun-like stars in the habitable zone, where temperatures are right for possible lakes and oceans of water. To find the planets, Kepler will stare at one large expanse of sky for the duration of its lifetime, looking for periodic dips in starlight that occur as planets circle in front of their stars and partially block the light. Its 95-megapixel camera, the largest ever launched into space, can detect tiny changes in a star's brightness of only 20 parts per million. Images from the camera are intentionally blurred to minimize the number of bright stars that saturate the detectors. While some of the slightly saturated stars are candidates for planet searches, heavily saturated stars are not. "Everything about Kepler has been optimized to find Earth-size planets," said James Fanson, Kepler's project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Our images are road maps that will allow us, in a few years, to point to a star and say a world like ours is there." Scientists and engineers will spend the next few weeks calibrating Kepler's science instrument, the photometer, and adjusting the telescope's alignment to achieve the best focus. Once these steps are complete, the planet hunt will begin. "We've spent years designing this mission, so actually being able to see through its eyes is tremendously exciting," said Eric Bachtell, the lead Kepler systems engineer at Ball Aerospace & Technology Corp. in Boulder, Colo. Bachtell has been working on the design, development and testing of Kepler for nine years. Kepler is a NASA Discovery mission. Ames is responsible for the ground system development, mission operations and science data analysis. JPL manages the Kepler mission development. Ball Aerospace & Technologies Corp. is responsible for developing the Kepler flight system and supporting mission operations. For images, animations and more information about the Kepler mission, visit: http://www.nasa.gov/kepler
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 The Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations ( CALIPSO) satellite has resumed operations after switching from its primary to its backup laser nearly three years after the launch of a satellite that is helping scientists solve the puzzle of how clouds and aerosols affect Earth's climate. The backup laser was designed into CALIPSO to make it robust, in case the primary laser became unreliable. The value of the planning came to the forefront early this year as the primary laser began to behave erratically, due to a slow pressure leak in the laser's canister. The leak was known about since prior to launch, and likely came about during fabrication. The CALIPSO team, a joint effort between NASA and Centre National d'Etudes Spatiales (CNES), worked together to start up the backup laser, which hadn't been used in three years. It provided its " first light" aerosol and cloud vertical profiles on Mar. 12. The instrument then resumed normal operations and is undergoing a calibration review now. The release of standard data products should resume in late April, and once data is re-processed the total gap due to the switch will be about 10 days. CALIPSO provides a unique vertical profile measurement of clouds and aerosols using space-borne Light Detection and Ranging – or, lidar. Integrated with other measurements from a constellation of five satellites, one from France and four from NASA, called the A-Train, CALIPSO's observations are improving our understanding of two poorly understood variables in Earth's changing climate: aerosols and clouds and their interactions. CALIPSO's near-simultaneous measurements with the other instruments can be integrated with and also enhance data gathered by satellites such as CloudSat.  "This mission continues to be a success," said Chip Trepte, CALIPSO's project scientist, based at NASA's Langley Research Center. "We completed the objectives of the prime mission, which were to determine the location and frequency of clouds and aerosol layers over the globe and some of their properties, through at least three years. CALIPSO is filling a measurement gap that other satellite missions are unable to provide." After an April 2006 launch, CALIPSO's primary laser began operating in June 2006, soon demonstrating the ability to observe and track clouds and aerosols as they change over time. The primary laser collected nearly three years, i.e., 12 seasons, of data. The backup laser appears to be healthy and able to last at least that long, barring unforeseen problems. "Even though we are on each side of the Atlantic, we work as a single, integrated NASA-CNES team," said Nadège Quéruel, mission operations manager with the CNES team. CNES and NASA worked together to successfully manage the problems with the first laser and to transition to the second laser with only minor effect on the CALIPSO data record. Trepte said the CALIPSO team was aware before launch that the laser canister was losing pressure. But the leak was so slow it was expected the primary laser could still complete much of the three-year, prime mission. "We were not surprised," Trepte said. "The good news is, we turned on the second laser that had been idle three years, and it's working. We built a redundant system to make sure we'd be able to continue making these important measurements." With humankind's burning of fossil fuels and other activities altering Earth's atmosphere and climate, scientists are using satellites such as CALIPSO to better understand the complexities of the atmosphere's structure and composition, its behavior and our impact on it as well as its impact on society. CALIPSO has expanded that quest by providing measurements to compare with models and thereby become an essential component of improving climate models. CALIPSO provides a curtain of profile measurements along the satellite track and can measure aerosols and clouds during day and night. Aerosols are tiny suspended liquid or solid particles that appear to the human eye as dust, smoke and haze. Many natural sources produce aerosols: the oceans send sea salt into the air, winds kick up dust clouds, and wildfires create massive smoke and haze plumes. Industrial processes and agricultural burning by humans also create aerosols in large enough quantity to alter clouds, precipitation, the earth's energy budget and, ultimately, the climate. A NASA-led report released earlier this year said that our understanding of human-produced aerosols' climate change impacts remains inadequately understood, and scientists should seek to dramatically reduce the uncertainty of aerosol influence on climate change. Scientists around the world have also used CALIPSO data to learn more about air quality and pollution, illuminating air quality conditions such as the summer smog that blankets the Tibetan Plateau. "We're seeing rivers of aerosols and dust coming and going," Trepte said. "Not only are we making important aerosol measurements, we've been able to map very thin clouds that affect how sunlight is absorbed or reflected, on a global basis." While nearly three years of measurements has been a great start, the backup laser allows the mission to continue and build on a record that becomes more helpful the longer it gets. "It's one thing to get the measurements. It's another to capture the variability," Trepte said.  CALIPSO's primary laser generated more than 1.6 billion laser pulses and more than 20 terabytes of data. CALIPSO observations have been used to characterize the large effects of smoke located over clouds in warming the atmosphere. Conventional satellite instruments are unable to measure aerosols located above clouds and their effects were only estimated before this. The mission's data have been used to test measurements of clouds from conventional satellite sensors and improve the accuracy of these data, which will lead to advances in weather forecasting and climate prediction. And CALIPSO observations have given us a greatly improved knowledge of polar stratospheric clouds – clouds which form high in the atmosphere over the poles during the winter and play a major role in the formation of the ozone hole over Antarctica. "The performance of CALIPSO's lidar instrument is also a benchmark in and of itself," Trepte said. "It's the first laser system that has operated in space this long, continuously, for atmospheric measurements."
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Announcement on 'Colbert Report,' Treadmill Named COLBERTThe International Space Station module formerly known as Node 3 has a new name. After receiving more than a million responses in an online poll, NASA is naming the node " Tranquility."  The name Tranquility was chosen from thousands of suggestions submitted by participants on www.nasa.gov. The "Help Name Node 3" poll asked people to vote for the module's name either by choosing one of four options listed by NASA or offering their own suggestion. Tranquility was one of the top ten suggestions submitted by respondents to the poll, which ended March 20. "The public did a fantastic job and surprised us with the quality and volume of the suggestions," said Bill Gerstenmaier, associate administrator for Space Operations. "Apollo 11 landed on the moon at the Sea of Tranquility 40 years ago this July. We selected 'Tranquility' because it ties it to exploration and the moon, and symbolizes the spirit of international cooperation embodied by the space station." NASA announced the name Tuesday with the help of Expedition 14 and 15 astronaut Suni Williams on Comedy Central's "The Colbert Report." The show's producers offered to host the name selection announcement after comedian Stephen Colbert took an interest in the poll and urged his viewers to suggest the name "Colbert," which received the most entries. "We don't typically name U.S. space station hardware after living people and this is no exception," Gerstenmaier joked. "However, NASA is naming its new space station treadmill the 'Combined Operational Load Bearing External Resistance Treadmill,' or COLBERT. We have invited Stephen to Florida for the launch of COLBERT and to Houston to try out a version of the treadmill that astronauts train on." The treadmill is targeted to launch to the station in August. It will be installed in Tranquility after the node arrives at the station next year. A newly-created patch will depict the acronym and an illustration of the treadmill.  Tranquility is scheduled to arrive at NASA's Kennedy Space Center in Florida in May. There, it will be prepared for space shuttle Endeavour's flight, designated STS-130, which is targeted for launch in February 2010. Tranquility will join four other named U.S. modules on the station: the Destiny laboratory, the Quest airlock, the Unity node and the Harmony node. Tranquility is a pressurized module that will provide room for many of the space station's life support systems. Attached to the node is a cupola, which is a unique work station with six windows on the sides and one on top. Suni Williams made the announcement on "The Colbert Report" two years after running the Boston Marathon in space on a station treadmill similar to COLBERT.
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NASA satellite data and a new modeling approach could improve weather forecasting and save more lives when future cyclones develop. About 15 percent of the world’s tropical cyclones occur in the northern Indian Ocean, but because of high population densities along low-lying coastlines, the storms have caused nearly 80 percent of cyclone-related deaths around the world. Incomplete atmospheric data for the Bay of Bengal and Arabian Sea make it difficult for regional forecasters to provide enough warning for mass evacuations. In the wake of last year’s Cyclone Nargis -- one of the most catastrophic cyclones on record -- a team of NASA researchers re-examined the storm as a test case for a new data integration and mathematical modeling approach. They compiled satellite data from the days leading up to the May 2 landfall of the storm and successfully " hindcasted" Nargis' path and landfall in Burma. " Hindcasting" means that the modelers plotted the precise course of the storm. In addition, the retrospective results showed how forecasters might now be able to produce multi-day advance warnings in the Indian Ocean and improve advance forecasts in other parts of the world. Results from their study were published March 26 in Geophysical Research Letters. "There is no event in nature that causes a greater loss of life than Northern Indian Ocean cyclones, so we have a strong motivation to improve advance warnings," said the study’s lead author, Oreste Reale, an atmospheric scientist with the Goddard Earth Sciences and Technology Center, a partnership between NASA and the University of Maryland-Baltimore County. In late April 2008, weather forecasters tracking cyclone Nargis initially predicted the storm would make landfall in Bangladesh. But the storm veered unexpectedly to the east and intensified from a category 1 storm to a category 4 in just 24 hours. When it made landfall in Burma (Myanmar) on May 2, the storm and its surge killed more than 135,000 people, displaced tens of thousands, and destroyed about $12 billion in property. In the months that followed, Reale and his U.S.-based team tested the NASA-created Data Assimilation and Forecasting System known as GEOS-5 and its NASA/NOAA-created analysis technique using data from the days leading up to Nargis because the storm was particularly fatal and highly characteristic of cyclones in the northern Indian Ocean. Cyclones in the Bay of Bengal – stretching from the southern tip of India to Thailand – are particularly difficult to analyze because of " blind spots" in available atmospheric data for individual storms, as well as the small dimensions of the Bay, which ensure that storms do not have much time to develop or circulate. In most instances, regionally strong wind shear suppresses cyclone development. But when tropical cyclones do form, flooding waves and storm surges can quickly reach the narrow basin’s shores. And that unusual wind shear, which is fueled by large temperature contrasts between sea and land, can also lead to erratic storm tracks. Forecasting is also made particularly difficult by the " blind spots," Reale noted. Land-based weather stations monitor the edges of the bay, but they cannot see much when a storm is brewing several hundred miles from the coastline. Forecasters from the India Meteorological Department and the U.S. Navy’s Joint Typhoon Warning Center lack access to the fleet of " hurricane hunting" airplanes that fly through Atlantic storms. They have to rely on remote satellite measurements that can only assess atmospheric and ocean temperatures under " clear-sky," or cloudless, conditions -- not exactly common in the midst of a cyclone. In their modeling experiment, Reale’s team detected and tracked Nargis’ path by employing novel 3-dimensional satellite imagery and atmospheric profiles from the Atmospheric Infrared Sounder ( AIRS) instrument aboard NASA’s Aqua satellite to see into the heart of the storm. AIRS has become increasingly important to weather forecasting because of its ability to show changes in atmospheric temperature and moisture at varying altitudes. Until recently, many weather modelers were only using AIRS data from cloud-free skies. In 2007, atmospheric scientist Joel Susskind of NASA Goddard Space Flight Center, Greenbelt, Md., successfully demonstrated through a technique developed by NASA research scientist Moustafa Chahine that accurate atmospheric temperatures could be obtained using real (versus hypothetical data in a 2003 Susskind study) AIRS partly-cloudy data. Reale’s team used the temperature data products from Susskind’s work to run the NASA model with the added information from partially-cloudy areas of sky that traditionally got left out. AIRS cloudy-sky data can now be integrated into what are called shared data assimilation systems, which combine millions of data points from Earth-observing satellites, instrumented ocean buoys, ground-based sensors, aircraft-based instruments, and man-on-the-scene observations. Data assimilation transforms the data into digital local maps that models can " read" to produce either hindcasts or advance projections of future weather conditions. Lau, chief of Goddard’s Laboratory for Atmospheres, believes that regional forecasting agencies monitoring the region can readily access AIRS’ data daily and optimize forecasts for cyclones in the Indian Ocean. According to Lau, the same technique can be useful to forecasts of hurricanes in the Atlantic and typhoons in the western Pacific, particularly when the storm is formed over open oceans out of flight range of hurricane-hunting airplanes. "With this approach, we can now better define cyclones at the early stages and track them in the models to know what populations may be most at risk," explained Reale. "And every 12 hours we gain in these forecasts means a gain in our chances to reduce loss of life." Related Links:> NASA's Hurricane/Tropical Cyclone Web Site> NASA’s AIRS Instrument> Images of Cyclone Nargis from Space> How Do Tropical Cyclones Form?> NASA Study Finds 'Pre-Existing Condition' Fueled Killer Cyclone
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 What if solar physicists could predict sun storms with the same accuracy and efficiency that meteorologists predict hurricanes? In much the same way that satellites allow forecasters to see the inner workings and development of a hurricane from its origins until the moment it reaches shore, NASA’s STEREO spacecraft are now capturing images of solar storms and making real-time measurements of their magnetic fields from the moment they lift off the sun until the moment their pressure waves reach Earth's shores. Eruptions from the sun’s outer atmosphere, or corona, can wreak havoc on earthly technology. These solar hurricanes, known as coronal mass ejections ( CMEs), spew billions of tons of plasma into space at thousands of miles per hour and carry some of the sun’s magnetic field with it.  These solar storm clouds create a shock wave and a large, moving disturbance in the solar system. The shock can accelerate some of the particles in space to high energies, a form of "solar cosmic rays" that can be hazardous to spacecraft and astronauts. The CME material, which arrives days later, can disrupt Earth’s magnetic field, or magnetosphere, and upper atmosphere. Observations from NASA’s twin Solar Terrestrial Relations Observatory ( STEREO) spacecraft have allowed scientists to accurately measure for the first time the speed, trajectory, and three-dimensional shape of solar storms. STEREO consists of two nearly identical observatories that make simultaneous observations of CMEs from two different vantage points. One observatory 'leads' Earth in its orbit around the sun, while the other observatory 'trails' the planet. STEREO’s two vantage points provide a unique view of the anatomy of a solar storm as it evolves and travels toward Earth. Once the CME arrives at the orbit of Earth, sensors on the satellites take in situ measurements of the solar storm cloud, providing a "ground truth" between what was seen at a distance and what is real inside the CME. The combination is providing solar physicists with the most complete understanding to date of the inner workings of these storms. It also represents a big step toward predicting when and how the impact will be felt at Earth. The separation angle between the satellites affords researchers to track a CME in three dimensions, something they have done several times in the past few years as they have learned to use this new space weather tool. "We can now see a CME from the time it leaves the solar surface until it reaches Earth, and we can reconstruct the event in 3D directly from the images," said Angelos Vourlidas, a solar physicist at the Naval Research Laboratory, Washington, and project scientist for the Sun Earth Connection Coronal and Heliospheric Investigation aboard STEREO. "The in situ measurements from STEREO and other near-Earth spacecraft link the physical properties of the escaping CME to the remote images," said Antoinette "Toni" Galvin, a solar physicist at the University of New Hampshire, and the principal investigator on STEREO’s Plasma and Suprathermal Ion Composition ( PLASTIC) instrument. "This helps us to understand how the internal structure of the CME was formed and to better predict its impact on Earth." Until now, CMEs could be imaged near the sun but the next measurements had to wait until the CME cloud arrived at Earth three to seven days later. STEREO’s real-time images and measurements give scientists a slew of information—speed, direction, and velocity—of a CME days sooner than with previous methods. As a result, more time is available for power companies and satellite operators to prepare for potentially damaging solar storms. Much like a hurricane’s destructive force depends on its direction, size, and speed, the seriousness of a CME’s effects depends on its size and speed, as well as whether it makes a direct or oblique hit across Earth’s orbit. CMEs disturb the space dominated by Earth's magnetic field. Disruptions to the magnetosphere can trigger the brightly colored, dancing lights known as auroras, or Northern and Southern Lights. While these displays are harmless, they indicate that Earth’s upper atmosphere and ionosphere are in turmoil. Sun storms can interfere with communications between ground stations and satellites, airplane pilots, and astronauts. Radio noise from a storm can also disrupt cell phone service. Disturbances in the ionosphere caused by CMEs can distort the accuracy of Global Positioning System ( GPS) navigation and, in extreme cases, induce stray electrical currents in long cables and power transformers on the ground. The twin STEREO spacecraft were launched October 25, 2006, into Earth’s orbit around the sun. The mission is the third in NASA’s Solar Terrestrial Probes ( STP) program.
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 The parachute for NASA's Mars Science Laboratory passed flight-qualification testing in March and April 2009 inside the world's largest wind tunnel, at NASA Ames Research Center, Moffett Field, Calif. In this image, an engineer is dwarfed by the parachute, the largest ever built to fly on an extraterrestrial flight. It is designed to survive deployment at Mach 2.2 in the Martian atmosphere, where it will generate up to 65,000 pounds of drag force. The parachute, built by Pioneer Aerospace, South Windsor, Conn., has 80 suspension lines, measures more than 50 meters (165 feet) in length, and opens to a diameter of nearly 16 meters (51 feet). The wind tunnel is 24 meters (80 feet) tall and 37 meters (120 feet) wide, big enough to house a Boeing 737. It is part of the National Full-Scale Aerodynamics Complex, operated by the U.S. Air Force, Arnold Engineering Development Center. NASA's Jet Propulsion Laboratory, Pasadena, Calif., is building and testing the Mars Science Laboratory spacecraft for launch in 2011. The mission will land a roving analytical laboratory on the surface of Mars in 2012. JPL is a division of the California Institute of Technology.
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The International Space Station module formerly known as Node 3 has a new name. After more than a million online responses, the node will be called " Tranquility." The name Tranquility was chosen from thousands of suggestions submitted by participants on NASA's Web site, www.nasa.gov. The "Help Name Node 3" poll asked people to vote for the module's name either by choosing one of four options listed by NASA or offering their own suggestion. Tranquility was one of the top ten suggestions submitted by respondents to the poll, which ended March 20. "The public did a fantastic job and surprised us with the quality and volume of the suggestions," said Bill Gerstenmaier, associate administrator for Space Operations.
 "Apollo 11 landed on the moon at the Sea of Tranquility 40 years ago this July. We selected 'Tranquility' because it ties it to exploration and the moon, and symbolizes the spirit of international cooperation embodied by the space station." "We don't typically name U.S. space station hardware after living people and this is no exception," Gerstenmaier joked. "However, NASA is naming its new space station treadmill the 'Combined Operational Load Bearing External Resistance Treadmill,' or COLBERT. We have invited Stephen to Florida for the launch of COLBERT and to Houston to try out a version of the treadmill that astronauts train on." The treadmill is targeted to launch to the station in August. It will be installed in Tranquility after the node arrives at the station next year. A newly-created patch will depict the acronym and an illustration of the treadmill. Tranquility is scheduled to arrive at NASA's Kennedy Space Center in Florida in May. There, it will be prepared for space shuttle Endeavour's flight, designated STS-130, which is targeted for launch in February 2010. Tranquility will join four other named U.S. modules on the station: the Destiny laboratory, the Quest airlock, the Unity node and the Harmony node. Tranquility is a pressurized module that will provide room for many of the space station's life support systems. Attached to the node is a cupola, which is a unique work station with six windows on the sides and one on top. Tranquility is targeted for launch in late 2009. Suni Williams made the announcement on "The Colbert Report" two years after running the Boston Marathon in space on a station treadmill similar to COLBERT. For more information about the station and the Tranquility module, visit: http://www.nasa.gov/station For more information about the Apollo 11 anniversary, visit: http://www.nasa.gov/apollo40th
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In the 50 years that NASA has been in the space game, it has scored a long string of triumphs in spaceflight and the exploration of distant worlds and the cosmos. No less impressive is NASA's record of wins for the home team: planet Earth and all of us living on it. With a strong roster of globe-circling satellites, flying labs, advanced computing, and scientists and engineers, NASA has led the way in seeing a whole new Earth and understanding our responsibility for its future. Last year, the National Academy of Sciences cataloged the biggest achievements gained from five decades of observing Earth from space. NASA played a big part in these accomplishments that have changed our world. Which ones do you think are NASA's biggest hits? You can vote here for up to three of the accomplishments below. The poll closes at 4 p.m. EDT on April 21. Results will be announced on Earth Day, April 22.
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| From Storm-Spotting to Next Week's WeatherSince the beginning of the space age, NASA has been at the forefront of using Earth orbit to get a better view of how weather systems develop. And now the world is a safer place to live in when it comes to dangerous weather. It has been decades since a hurricane or tropical cyclone has gone undetected before it struck land. NASA helped to build and launch an armada of orbiting sensors (more are in the works) that detect a growing number of factors that drive the world's weather. The result: seven-day forecasts have vastly improved over the past three decades. (Image: Hurricane Katrina, 2005, NASA's Tropical Rainfall Measuring Mission)› Go to Voting Page |  > Larger image
| It's a Big Green WorldAnd now we can see it all -- green plants large and small, on land and on the sea, all over the globe. Ecology is now a truly worldwide undertaking, thanks to NASA's pioneering work in developing space-based instruments that can measure the greenness of chlorophyll in plants. We can track widespread changes in ecosystems, like the increasing growing season in the far north and the rise and fall of ocean algae and fisheries associated with El Nino events. And we can see how big a part ecosystems play in the ongoing cycling of carbon dioxide in and out of the atmosphere. (Image: From NASA's Sea-viewing Wide Field-of-view Sensor onboard the SeaStar spacecraft; NASA Goddard, the SeaWiFS Project, GeoEye)› Go to Voting Page |  > Larger image
| The Global Reach of Air PollutionAir pollution was once thought of as just a local problem. But global views from space by NASA and other space agencies confirmed that pollution can move from country to country and even across oceans. In the 1980s the first maps of ozone pollution low in the atmosphere, where it is a health hazard, drew attention to human impacts on the atmosphere such as agricultural fires and land-use changes in the tropics. Newer satellite views show plumes of pollution crossing oceans. (Image: Alaskan wildfires, 2004; NASA's Terra, Moderate Resolution Imaging Spectroradiometer; Jacques Descloitres, NASA Goddard)› Go to Voting Page |  > Larger image
| The Ultimate Home Energy Audit
NASA led the way in building the Earth-orbiting tools to conduct the world's largest home energy audit: tracking the flow of energy into and out of the whole Earth system. With this big picture view, we've measured changes in the sun's energy output reaching Earth (pretty small) and the amount of energy redirected away from Earth after a massive volcano erupted into the stratosphere (a lot, but not for long). With this inventory of the natural factors that heat and cool the planet, we get a better fix on the role humans play in altering climate. (Image: Hurricane system cools Earth by reflecting sunlight (left, white/green areas) and warms it by trapping outgoing heat (right, blue/white); NASA's Aqua, Clouds and the Earth's Radiant Energy System instrument; NASA Langley)
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| Warming and Rising SeasIt's a good thing NASA began keeping an eye on the temperature of the world's ocean surface in the 1970s. Without the continuous record of sea surface temperature since then by National Oceanic and Atmospheric Administration satellites (designed and launched by NASA), scientists would not have a key piece of evidence for global warming: most of the extra heat is absorbed in the oceans. And this isn't good news for rising sea levels -- water expands when it gets warmer, adding to rising seas around the world. (Image: Warm waters of the Gulf Stream, 2001; NASA's Terra, Moderate Resolution Imaging Spectroradiometer; Liam Gumley, University of Wisconsin-Madison)› Go to Voting Page |  > Larger image
| Finding Your WayBehind the power of today's GPS units to get you where you need to go is a huge body of scientific knowledge about our spinning, shifting Earth. We live on an active planet where every piece of real estate moves relative to each other. Precise navigation with GPS satellites would be impossible without ultra-precise knowledge of Earth's shape and how it rotates. NASA pioneered much of this work with a global network of laser ranging satellites and super-charged GPS receivers to monitor daily changes in Earth’s surface. Oh, and there are side benefits like tracking the movement of tectonic faults, measuring sea level rise, and making air travel safer. (Image: NASA's Laser Geodynamics Satellite, LAGEOS I, launched 1976.)› Go to Voting Page |  > Larger image
| Ice Sheets on the Move
The massive polar ice sheets, a big piece of Earth's climate puzzle once too remote and forbidding for detailed study, have recently yielded a disturbing secret: they are shrinking. Satellite watchdogs from NASA, Europe and Canada have shown that they are losing massive amounts of ice at outlet glaciers. In addition, the floating ice shelves that buttress these glaciers are prone to failure. Many now see these changes as the "canary in the coal mine" of what global warming can do to Earth, including the possibility of a rapid rise in sea level. (Image: Antarctica's Larsen B Ice Shelf, 2002; NASA's Terra, Moderate Resolution Imaging Spectroradiometer; Ted Scambos, National Snow and Ice Data Center, University of Colorado)
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| Predicting Feast or FamineIn the 1970s the U.S. Geological Survey and NASA developed a satellite instrument that could pick out different types of large-scale agricultural crops and map their location. Scientists used this tool to estimate the size of annual yields of wheat, corn, soybeans, and other crops, providing a new way to forecast food shortages (and surpluses) around the world. Federal agencies now routinely use satellite imagery from NASA and others in crop commodity forecasting of all major grains. (Image: Crop circles in Kansas, 2001; NASA's Terra, Advanced Spaceborne Thermal Emission and Reflection Radiometer; NASA Goddard, METI, ERSDAC, JAROS, U.S./Japan ASTER Science Team)› Go to Voting Page |  > Larger image
| A Lively Water World
Scientists had only a fuzzy picture of the world's changing oceans before NASA joined forces with the French Space Agency to measure the height of the sea surface from space. The new satellites uncovered a topsy-turvy water world full of tiny eddies that mix and churn and the grand-daddy of all ocean phenomena: El Nino. This big-time ocean event -- lasting more than a year and stretching halfway around the world -- changes weather and climate across the globe. The view from space revealed a dynamic ocean that shapes our climate and a rise in sea level three times faster than a century ago. (Image: High and low areas of the world's oceans (red and blue, respectively), 2009; Jason-1 and Ocean Surface Topography Mission on Jason-2; NASA Jet Propulsion Laboratory, CNES, CLS, DUACS)
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| Diagnosing Our Ailing Ozone Layer
NASA satellites and aircraft provided critical evidence in the international diagnosis of Earth’s ozone layer. With scientific proof of how certain manmade chemicals were destroying the protective ozone layer high in the stratosphere, the nations of the world acted to ban the culprits. Scientists now so thoroughly understand the ingredients of the chemical brew and the atmospheric conditions producing ozone damage that they can predict when the ozone hole over Antarctica will recover (look for it around 2070). (Image: Ozone hole over Antarctica, 2007; NASA's Aura, Ozone Monitoring Instrument)
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 The team operating NASA's Mars Exploration Rover Spirit is examining data received from Spirit in recent days to diagnose why the rover apparently rebooted its computer at least twice over the April 11-12 weekend. "While we don't have an explanation yet, we do know that Spirit's batteries are charged, the solar arrays are producing energy and temperatures are well within allowable ranges. We have time to respond carefully and investigate this thoroughly," said John Callas of NASA's Jet Propulsion Laboratory, Pasadena, Calif., project manager for Spirit and twin-rover Opportunity. "The rover is in a stable operations state called automode and taking care of itself. It could stay in this stable mode for some time if necessary while we diagnose the problem." Spirit communicated with controllers Friday, Saturday and Sunday, but some of the communication sessions were irregular. One of the computer resets apparently coincided in timing with operation of the rover's high-gain dish antenna. The rover team has the advantage of multiple communication options. Spirit can communicate directly with Earth via either the pointable high-gain antenna or, at a slower data rate, through a low-gain antenna that does not move. Additionally, communications can be relayed by Mars orbiters, using the UHF ( ultra-high frequency) transceiver, a separate radio system on the rover. "To avoid potential problems using the pointable antenna, we might consider for the time being just communicating by UHF relay or using the low-gain antenna," Callas said. Spirit finished its three-month prime mission on Mars five years ago and has kept operating through multiple mission extensions. The rover's onboard software has been updated several times to add new capabilities for the mission, most recently last month. The team is investigating whether the unexpected behavior in recent days could be related to the new software, but the same software is operating on Opportunity without incident. "We are aware of the reality that we have an aging rover, and there may be age-related effects here," Callas said. In the past five weeks, Spirit has made 119 meters (390 feet) of progress going counterclockwise around a low plateau called " Home Plate" to get from the place where it spent the past Martian winter on the northern edge of Home Plate toward destinations of scientific interest south of the plateau. On March 10, after several attempts to get past obstacles at the northeastern corner of Home Plate, the rover team decided to switch from a clockwise route to the counterclockwise one. Subsequent events have included Spirit's longest one-day drive since the rover lost use of one of its wheels three years ago, plus detailed inspection of light-toned soil exposed by the dragging of the inoperable wheel. Halfway around Mars, meanwhile, Opportunity has continued progress on a long-term trek toward Endeavour Crater, a bowl 22 kilometers (14 miles) in diameter and still about 12 kilometers (7 miles) away. Last week, a beneficial wind removed some dust from Opportunity's solar array, resulting in an increase by about 40 percent in the amount of electrical output from the rover's solar panels. JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA's Science Mission Directorate, Washington.
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 A flare-up in a jet of matter blasting from a monster black hole is giving astronomers an incredible light show. The outburst is coming from a blob of matter, called HST-1, embedded in the jet, a powerful narrow beam of hot gas produced by a supermassive black hole residing in the core of the giant elliptical galaxy M87. HST-1 is so bright that it is outshining even M87’s brilliant core, whose monster black hole is one of the most massive yet discovered. The glowing gas clump has taken astronomers on a rollercoaster ride of suspense. Astronomers watched HST-1 brighten steadily for several years, then fade, and then brighten again. They say it’s hard to predict what will happen next.
NASA’s Hubble Space Telescope has been following the surprising activity for seven years, providing the most detailed ultraviolet-light view of the event. Other telescopes have been monitoring HST-1 in other wavelengths, including radio and X-rays. The Chandra X-ray Observatory was the first to report the brightening in 2000. HST-1 was first discovered and named by Hubble astronomers in 1999. The gas knot is 214 light-years from the galaxy’s core. The flare-up may provide insights into the variability of black hole jets in distant galaxies, which are difficult to study because they are too far away. M87 is located 54 million light-years away in the Virgo Cluster, a region of the nearby universe with the highest density of galaxies. “I did not expect the jet in M87 or any other jet powered by accretion onto a black hole to increase in brightness in the way that this jet does,” says astronomer Juan Madrid of McMaster University in Hamilton, Ontario, who conducted the Hubble study. “It grew 90 times brighter than normal. But the question is, does this happen to every single jet or active nucleus, or are we seeing some odd behavior from M87?” Hubble gives astronomers a unique near-ultraviolet view of the flare that cannot be accomplished with ground-based telescopes. “ Hubble’s sharp vision allows it to resolve HST-1 and separate it from the black hole,” Madrid explains. Despite the many observations by Hubble and other telescopes, astronomers are not sure what is causing the brightening. One of the simplest explanations is that the jet is hitting a dust lane or gas cloud and then glows due to the collision. Another possibility is that the jet’s magnetic field lines are squeezed together, unleashing a large amount of energy. This phenomenon is similar to how solar flares develop on the Sun and is even a mechanism for creating Earth’s auroras. The disk around a rapidly spinning black hole has magnetic field lines that entrap ionized gas falling toward the black hole. These particles, along with radiation, flow rapidly away from the black hole along the magnetic field lines. The rotational energy of the spinning accretion disk adds momentum to the outflowing jet. Madrid assembled seven year’s worth of Hubble archival images of the jet to capture changes in the HST-1’s behavior over time. Some of the images came from observing programs that studied the galaxy, but not the jet. He found data from the Space Telescope Imaging Spectrograph ( STIS) that showed a noticeable brightening between 1999 and 2001. In images from 2002 to 2005, HST-1 continued to rise steadily in brightness. In 2003 the jet knot was more brilliant than M87’s luminous core. In May 2005 HST-1 became 90 times brighter than it was in 1999. After May 2005 the flare began to fade, but it intensified again in November 2006. This second outburst was fainter than the first one. “By watching the outburst over several years, I was able to follow the brightness and see the evolution of the flare over time,” Madrid says. “We are lucky to have telescopes like Hubble and Chandra, because without them we would see the increase in brightness in the core of M87, but we would not know where it was coming from.” Madrid hopes that future observations of HST-1 will reveal the cause of the mysterious activity. “We hope the observations will yield some theories that will give us some good explanations as to the mechanism that is causing the flaring,” Madrid says. “ Astronomers would like to know if this is an intrinsic instability of the jet when it plows its way out of the galaxy, or if it is something else.” The study’s results are published in the April 2009 issue of the Astronomical Journal. The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency ( ESA) and is managed by NASA's Goddard Space Flight Center (GSFC) in Greenbelt, Md. The Space Telescope Science Institute ( STScI) conducts Hubble science operations. The institute is operated for NASA by the Association of Universities for Research in Astronomy, Inc., Washington, D.C.
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 More than 10,000 students from 28 countries and 533 custom-built robots will swarm Atlanta's Georgia Dome, April 16-18, to compete in the FIRST ( For Inspiration and Recognition of Science and Technology) Championship, and discover the excitement of science and technology. Students engage in three robotics competitions under one roof: FIRST Robotics Competition, FIRST Tech Challenge and FIRST LEGO® League. "Today, facing the challenges of our fragile global economy and climate change, and addressing worldwide public health concerns, we need innovative thinkers to help solve society’s increasingly-complex problems," said the competition's founder Dean Kamen. "Handling robotics challenges and working alongside professional engineers, FIRST students develop the skills necessary to be the architects of the solutions we need." Kamen founded FIRST, a not-for-profit organization, to inspire young people's interest and participation in science, technology and engineering, and motivate them to pursue career opportunities in these fields. "We have 16-year-olds securing patents and 10-year-olds offering advice on climate change issues to government officials," Kamen continued. "I am encouraged to see so many positive contributions by FIRST students; each one of them is becoming his/her own economic stimulus package for the workforce of the future." Students vied for a spot at this weekend's FIRST Championship by competing in regional competitions for several months, displaying sportsmanship and excelling at competitive play. Along their journey, students learned business and marketing skills, as they secured sponsors and developed partnerships among schools, businesses and communities. Their hard work will culminate in three levels of robotics competitions during the FIRST Championship. The FIRST Robotics Competition ( FRC) Championship for high-school students is now in its 18th and largest-ever season. This year's challenge, " LUNACY," honors the 40th anniversary of Apollo 11, when NASA landed a man on the moon. In the " LUNACY" game, robots are designed to pick up 9" game balls and score them in trailers hitched to their opponents' robots for points during a two- minute and 15-second match. Additional points are awarded for scoring a special game ball, the "Super Cell," in the opponents' trailers during the last 20 seconds of the match. In January 2009, FRC teams viewed the game field and received a kit of parts made up of motors, batteries, a control system and a mix of automation components -- but no instructions. Working with mentors, students had six weeks to design, build, program and test their robots to meet the season's engineering challenge. Once these young inventors built a robot and a strategy to compete, their teams participated in regional competitions that measured the effectiveness of each robot, the power of collaboration, and the determination of the students. The FIRST Tech Challenge ( FTC) is a challenging mid-level robotics competition designed for high-school-age students who want a hands-on learning experience to develop and hone their skills and abilities in science, technology, engineering and math. The FTC World Championship features this year's game, "Face Off!," which was developed with input by professional robotics designers across the country. The challenge mirrors many real-world challenges that robotics engineers face today, such as navigating uneven surfaces, manipulating odd-shaped objects, using sensors to determine the environment and withstanding physical stress. FIRST LEGO League ( FLL) is a global robotics program for ages 9-14 (up to age 16 outside of the U.S. and Canada). This year's challenge is "Climate Connections." At the FLL World Festival, students will present their research and solutions for solving climate issues, and showcase LEGO MINDSTORMS robots using engineering concepts. To prepare for " Climate Connections," students learned about past, current and future climate conditions with team coaches and mentors; this allowed them to learn more about the science behind the challenge and to better understand the work of professionals in that field. Students who participate in FIRST are eligible nearly $10 million in scholarships from science and engineering schools across the U.S. More than 25 FIRST scholarship providers will be featured in Scholarship Row, where representatives will offer information about their schools' science and engineering programs. FIRST programs are implemented by 86,000 dedicated volunteers and supported by more than 3,000 corporate sponsors worldwide.
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The agency plans to make the announcement with the help of Expedition 14 and 15 astronaut Sunita "Suni" Williams on Comedy Central's "The Colbert Report." The program will air at 11:30 p.m. EDT. The name, which will not be publicly released until the program airs, was selected from thousands of unique suggestions submitted on NASA's Internet site, www.nasa.gov. The "Help Name Node 3" poll asked people to vote for the module's name either by choosing one of four NASA options or by offering their own suggestion. The poll closed on March 20. "The node naming poll was organic and took on a life of its own," said Bill Gerstenmaier, associate administrator for Space Operations at NASA Headquarters in Washington. "We received more than a million entries, in large part because social media Web sites and television programs, such as 'The Colbert Report,' took an interest. This spread overall awareness of the International Space Station." NASA originally planned to announce the node's name on April 28 after it arrived at NASA's Kennedy Space Center in Florida. However, the node's arrival at Kennedy is delayed until May, so the announcement moved to April 14. The show's producers offered to host the name selection announcement after comedian and host Stephen Colbert took interest during the census and urged his followers to post the name "Colbert." "I certainly hope NASA does the right thing," said Colbert. "Just kidding, I hope they name it after me." Node 3 is a pressurized module that will provide room for many of the space station's life support systems. Attached to the node is the cupola, a one-of-a-kind work station with six windows around the sides and one on top. Node 3 is targeted for launch in late 2009. For more information about the station and Node 3, visit: http://www.nasa.gov/station For more information about the node naming poll, visit: http://www.nasa.gov/externalflash/name_ISS/index.html For more information about "The Colbert Report," visit:
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NASA will hold a Science Update at 1 p.m. EDT, Tuesday, April 14, to present new findings and three-dimensional views revealing the inner workings of solar storms known as coronal mass ejections. The data will improve the ability to predict how and when these solar tsunamis impact Earth, affecting communication systems, power grids, and other technology. The briefing will take place in the James E. Webb Memorial Auditorium at NASA Headquarters, 300 E St., S.W., and will be carried live on NASA Television. Briefing participants are: -- Michael Kaiser, project scientist, Solar Terrestrial Relations Observatory ( STEREO), NASA's Goddard Space Flight Center in Greenbelt, Md. -- Angelos Vourlidas, project scientist, Sun Earth Connection Coronal and Heliospheric Investigation, Naval Research Laboratory in Washington -- Antoinette Galvin, principal investigator, Plasma and Suprathermal Ion Composition instrument, University of New Hampshire in Durham -- Madhulika Guhathakurta, STEREO program scientist, NASA Headquarters Reporters may ask questions from participating NASA locations or listen and ask questions by phone. For dial-in information, journalists should send an e-mail to j.d.harrington@nasa.gov listing name, media affiliation, and telephone number. For information about NASA TV, streaming video, downlink and schedule information, visit: http://www.nasa.gov/ntv
http://www.nasa.gov/stereo
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NASA astronaut Mike Massimino, a native of Franklin Square, N.Y., will be available for live interviews via satellite from 8 a.m. to 10 a.m. CDT on Monday, April 13. Massimino is training to fly on space shuttle Atlantis' mission to service the Hubble Space Telescope. Atlantis is targeted to launch from NASA's Kennedy Space Center in Florida on May 12. To participate, media should contact NASA's Johnson Space Center newsroom at 281-483-5111 by 1 p.m. on Friday, April 10. Mission Specialist Massimino is making his second visit to Hubble. He is one of seven astronauts who will fly on the space shuttle's fifth and final servicing mission to Hubble. The 11-day flight will include five spacewalks to make repairs and upgrades to the telescope, extending its life into the next decade. Massimino has been using Twitter to provide a unique, behind the scenes peek at the last weeks of his training. His Twitter username is Astro_Mike (@Astro_Mike). Along with Massimino, the crew of Atlantis includes Commander Scott Altman, Pilot Gregory C. Johnson and Mission Specialists Andrew Feustel, Michael Good, John Grunsfeld and Megan McArthur. To follow Massimino's Twitter, visit: http://twitter.com/Astro_Mike http://www.nasa.gov/shuttle
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NASA is known for launching rockets and exploring the universe, but some rocket scientists and aerospace engineers love to solve down-to-earth problems too. One of them is applying his knowledge to understanding the science of baseball. He isn't trying to give an edge to his home team. He's just using baseball to inspire students to exercise their brains.  Tom Benson, an aerospace engineer at NASA's Glenn Research Center in Cleveland, builds computer programs used to study hypersonic flight. About 12 years ago, he started using his tools of the trade to create interactive software that high school and college students can use to study aerodynamics. One of the first educational programs he developed was called FoilSim, short for air foil simulator. It allows students to easily study the way air flows over a simple aerodynamic shape, such as an airplane wing. After working with teachers and students for several years, Benson realized that he could make the physics of flight even easier to understand by comparing the wing to an object that most students find a little more familiar. He substituted a spinning ball for a fixed wing. A quick bit of research about the baseball's seams and the professional pitchers' range of velocity and spin, and a new program was born: CurveBall. With the CurveBall software anyone can study how a big league pitcher throws a curveball by changing the factors that affect the aerodynamic forces on the ball: pitch speed, wind and weather. These are the same forces that generate the lift of an aircraft wing. Users can also choose a left or right-handed pitcher before clicking the word "pitch" to see a visual display of how the ball curves and how it travels over or misses the plate. "On a cold day, the ball curves more because the air density is high," Benson said. "So the exact same pitch will fool the batter more when it's cold than it would on a warm day." Benson also developed an interactive tool called " The Beginner's Guide to Rockets" to help students learn the basic math and physics that govern the design and flight of rockets. Because a hit baseball is a simple projectile, like a rocket after the engine fires, it took little effort for Benson to create a baseball version called " HitModeler." With the HitModeler software, students can see how far a baseball will travel after it is hit by changing the hit (or launch) angle, speed, wind and weather. These are the same forces that determine how far a rocket will travel after launch. "If the air is thin, the ball doesn't curve as much. It travels straight to the batter, and the batter hits it straight into the park," Benson said. "That's part of the reason Denver's Coors Field is a hitter's park." Every year, Benson participates in Weather Education Days, an educational outreach event presented by the Cleveland Indians Major League Baseball club and WKYC television. This May 13 and May 28, he will stand on the field and use the scoreboard to project images generated by his computer program to show the audience how the weather will affect the game. "People who know me know that I love what I do," said Benson. "Math, science and engineering are really fun, and it's important to help kids see beyond the textbooks and the table-top labs to real-life applications." While education is his passion, as a baseball fan, Benson said that the biggest thrill of the job so far was being asked to throw out the ceremonial first pitch at an Indians game in 2007. "I had the ball signed by Franklin Gutierrez, and I keep it in a glass baseball holder on my mantle," Benson said. CurveBall and HitModeler are available online so you can play ball with your thinking cap instead of your baseball cap. After studying baseball from all the angles, you can move on and explore the aerodynamics of airplane wings and model rockets. "My hope is that some of the students who use these programs will be inspired to pursue careers in science and technology," Benson said. "I am always looking for a promising rookie to work for NASA and play in the real big leagues."
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NASA has exercised a $58 million, one-year extension option for a contract with S cience Applications International Corporation of Houston to provide support to safety and mission assurance activities at NASA's Johnson Space Center in Houston. The Safety and Mission Assurance Support Services contract helps ensure safety, reliability, maintainability, and quality in the International Space Station Program, the Space Shuttle Program and the Constellation Program. This cost-plus-award-fee contract option continues services from May 1, 2009, through April 30, 2010. Work under the contract will be performed at Johnson, NASA's Kennedy Space Center in Florida and at NASA's White Sands Test Facility in New Mexico. Significant subcontractors in the work include Futron Corp. of Bethesda, Md.; GHG of Houston; M.H. Chew of Livermore, Calif.; URS - Washington Division of Princeton, N.J.; Management Technology Associates of Huntsville, Ala.; J&P Technologies of Houston; JES Tech of Houston; SoHaR Incorporated of Culver City, Calif.; and Texas Southern University of Houston. For more information about NASA's Johnson Space Center, visit: http://www.nasa.gov/johnson
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 Astronomy Day events across the country find astronomers sharing their knowledge and passion about the night sky with others. Get ready for May 10th when you will find big celebrations, sidewalk astronomy, and a lot of star parties. It is a great time to bring your family out for a night together under the stars or a day of learning about the Sun. What if the person telling you about astronomy was only 13? Well, sometimes that is the case. Hear how the kids in these Night Sky Network clubs got their communities excited about the cosmos at last year's Astronomy Day and about one teacher's mission to get her students involved. Also find out how to participate this year. In Oklahoma, Eileen Grzybowski runs a high school club where the students do the presentations to the public. The Norman North Astronomy Club had a full Astronomy Day last year. Here she tells us about a small part of the activities they organized that day. "The students ran Star Lab shows in our portable Star Lab planetarium system at the top of the hour: 2, 3, and 4 p.m. (They added a 4:35 show by popular request!) The students who led the Star Lab shows received much applause for their presentations. They remarked that they got better at their storytelling after the first show. I told them, 'Just like teachers! Join the club!'" Katrina DeWitt tells us about making a scale model of the Universe as part of the Neville Public Museum Astronomical Society's Astronomy Day festivies in Wisconsin: "This was the first time I had used the Universe of Galaxies activity. Even I was amazed at how distant these objects really were. My eight-year-old son did most of the measuring (with a bit help from dad) and had a blast explaining to those that walked by, the scale model of our Universe." And in Tennessee, Jim Opalek of the Cumberland Astronomical Society tells us about how a dedicated teacher made a big difference for many of her students that day. "One woman made her way through the maze of telescopes and binoculars, asking questions about their operation and them, then introduced herself as a teacher. Later that afternoon and throughout the evening, we had many families come by who said they had received a phone call earlier that afternoon from their child's teacher, telling them they needed to come out and take advantage of the opportunity to observe through the telescopes and pick up some magazines and literature. This teacher needs to be commended for seizing the moment and making calls to her students on a Saturday afternoon. And as we helped each other pack up the scopes, tables, canopies and chairs, we wondered, could our guests possibly have gotten as much out of this as we did?" Jim, we bet they did. If you read about these activities and are wondering how you can get in on the fun this year, go ahead and contact your local astronomy club. See what they have in store for Astronomy Day this May 10th.
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 Though greenhouse gases are invariably at the center of discussions about global climate change, new NASA research suggests that much of the atmospheric warming observed in the Arctic since 1976 may be due to changes in tiny airborne particles called aerosols. Emitted by natural and human sources, aerosols can directly influence climate by reflecting or absorbing the sun's radiation. The small particles also affect climate indirectly by seeding clouds and changing cloud properties, such as reflectivity. A new study, led by climate scientist Drew Shindell of the NASA Goddard Institute for Space Studies, New York, used a coupled ocean-atmosphere model to investigate how sensitive different regional climates are to changes in levels of carbon dioxide, ozone, and aerosols. The researchers found that the mid and high latitudes are especially responsive to changes in the level of aerosols. Indeed, the model suggests aerosols likely account for 45 percent or more of the warming that has occurred in the Arctic during the last three decades. The results were published in the April issue of Nature Geoscience. Though there are several varieties of aerosols, previous research has shown that two types -- sulfates and black carbon -- play an especially critical role in regulating climate change. Both are products of human activity. Sulfates, which come primarily from the burning of coal and oil, scatter incoming solar radiation and have a net cooling effect on climate. Over the past three decades, the United States and European countries have passed a series of laws that have reduced sulfate emissions by 50 percent. While improving air quality and aiding public health, the result has been less atmospheric cooling from sulfates. At the same time, black carbon emissions have steadily risen, largely because of increasing emissions from Asia. Black carbon -- small, soot-like particles produced by industrial processes and the combustion of diesel and biofuels -- absorb incoming solar radiation and have a strong warming influence on the atmosphere. In the modeling experiment, Shindell and colleagues compiled detailed, quantitative information about the relative roles of various components of the climate system, such as solar variations, volcanic events, and changes in greenhouse gas levels. They then ran through various scenarios of how temperatures would change as the levels of ozone and aerosols -- including sulfates and black carbon -- varied in different regions of the world. Finally, they teased out the amount of warming that could be attributed to different climate variables. Aerosols loomed large. The regions of Earth that showed the strongest responses to aerosols in the model are the same regions that have witnessed the greatest real-world temperature increases since 1976. The Arctic region has seen its surface air temperatures increase by 1.5 C (2.7 F) since the mid-1970s. In the Antarctic, where aerosols play less of a role, the surface air temperature has increased about 0.35 C (0.6 F). That makes sense, Shindell explained, because of the Arctic's proximity to North America and Europe. The two highly industrialized regions have produced most of the world's aerosol emissions over the last century, and some of those aerosols drift northward and collect in the Arctic. Precipitation, which normally flushes aerosols out of the atmosphere, is minimal there, so the particles remain in the air longer and have a stronger impact than in other parts of the world. Since decreasing amounts of sulfates and increasing amounts of black carbon both encourage warming, temperature increases can be especially rapid. The build-up of aerosols also triggers positive feedback cycles that further accelerate warming as snow and ice cover retreat. In the Antarctic, in contrast, the impact of sulfates and black carbon is minimized because of the continent’s isolation from major population centers and the emissions they produce. "There's a tendency to think of aerosols as small players, but they're not," said Shindell. "Right now, in the mid-latitudes of the Northern Hemisphere and in the Arctic, the impact of aerosols is just as strong as that of the greenhouse gases." The growing recognition that aerosols may play a larger climate role can have implications for policymakers. "We will have very little leverage over climate in the next couple of decades if we're just looking at carbon dioxide," Shindell said. "If we want to try to stop the Arctic summer sea ice from melting completely over the next few decades, we're much better off looking at aerosols and ozone." Aerosols tend to be quite-short lived, residing in the atmosphere for just a few days or weeks. Greenhouses gases, by contrast, can persist for hundreds of years. Atmospheric chemists theorize that the climate system may be more responsive to changes in aerosol levels over the next few decades than to changes in greenhouse gas levels, which will have the more powerful effect in coming centuries. "This is an important model study, raising lots of great questions that will need to be investigated with field research," said Loretta Mickley, an atmospheric chemist from Harvard University, Cambridge, Mass. who was not directly involved in the research. Understanding how aerosols behave in the atmosphere is still very much a work-in-progress, she noted, and every model needs to be compared rigorously to real life observations. But the science behind Shindell’s results should be taken seriously. "It appears that aerosols have quite a powerful effect on climate, but there's still a lot more that we need to sort out," said Shindell. NASA’s upcoming Glory satellite is designed to enhance our current aerosol measurement capabilities to help scientists reduce uncertainties about aerosols by measuring the distribution and microphysical properties of the particles.
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 Commander Mike Fincke and Flight Engineer Yury Lonchakov of the 18th International Space Station crew landed in Kazakhstan at 3:16 a.m. EDT Wednesday after about six months in space. All three people aboard the Soyuz TMA-13 spacecraft were reported to be in good condition after their re-entry and landing. A Russian recovery team and NASA personnel reached the landing site by helicopter shortly after the Soyuz touched down. They helped the crew members into reclining chairs for medical tests and set up a medical tent nearby. With Fincke and Lonchakov was spaceflight participant Charles Simonyi. He launched to the station March 26 with the Expedition 19 crew, Commander Gennady Padalka and Flight Engineer Michael Barratt, under contract with the Russian Federal Space Agency. Japan Aerospace Exploration Agency ( JAXA) astronaut Koichi Wakata came to the station aboard space shuttle Discovery on its STS-119 mission, launched March 15. He served for the last part of Expedition 18 as a flight engineer. He remains aboard the station as a member of the Expedition 19 crew. Wakata is the first resident station crew member from JAXA. Expedition 18 crew members undocked their Soyuz spacecraft from the station at 11:55 p.m. Tuesday. The deorbit burn to slow the Soyuz and begin its descent toward the Earth took place at 2:24 a.m. Wednesday. When they landed, Fincke and Lonchakov had spent 178 days in space on their Expedition 18 flight, 176 of them on the station. Fincke, a colonel in the U.S. Air Force, returned from his second stay at the space station. He previously served as flight engineer and NASA Space Station science officer on Expedition 9 in 2004. Lonchakov, a colonel in the Russian Air Force, completed his third trip to the station. He was a mission specialist on STS-100, which visited the orbital outpost in 2001, and he returned to the station in 2002 as part of the Soyuz TMA-1 crew. › Read more about Expedition 19› Read more about Expedition 18 › View crew timelines
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 The first mirror segment that will fly on the James Webb Space Telescope, built by Northrop Grumman Corporation, has completed its first series of cryogenic temperature tests in the X-ray and Cryogenic Facility at the Marshall Space Flight Center in Huntsville, Ala. "We’re excited that we can support the James Webb Space Telescope with our world class cryogenic and x-ray telescope test facility," said Helen Cole, project manager for the Webb Telescope activities at NASA's Marshall Space Flight Center, Huntsville, Ala. "The test performed here are crucial to the success of the program since they’ll ensure the mirrors and components will be able to withstand the extreme cold temperatures of space." The mirror segment is the first of 18 flight mirror segments that will be joined to make a giant, 6.5-meter diameter (21.3 ft.) hexagonal mirror. The segments will be subject to temperatures of -414 degrees Fahrenheit in a 7,600 cubic-foot helium-cooled vacuum chamber at NASA Marshall. Engineers will measure how the mirror changes shape going from room temperature to cryogenic (frigid) temperatures, as the metal expands and contracts. They can model these changes to some extent, but not perfectly. The mirrors will be polished to about 100 nanometers (a human hair is approximately 60,000 to 120,000 nanometers) accuracy at room temperature, based on the expected changes. Then it will be cooled down to cryogenic temperatures and engineers will measure the mirror's surface, creating a " hit map" of unexpected changes. "This is what we have done so far with the first flight mirror segment," said Jonathan Gardner, Webb Telescope Deputy Project Scientist at NASA Goddard Space Flight Center, Greenbelt, Md. "Now, engineers will warm it up and polish out the "hit map" areas to get the mirror to 20 nanometer accuracy - a process which will take months. The mirrors will then be brought back down to cryogenic temperatures to verify the increased accuracy." In addition to this testing, engineers also did some " cryo cycling." That means going up and down in temperature (without polishing in between) to test the repeatability of the changes. Since there are 18 mirror segments, each measuring about 1.5 meters (4.9 ft.) in diameter, they will be tested in batches of six and chilled to cryogenic temperatures four times in a six-week time span. It takes approximately five days to cool a mirror segment to cryogenic temperatures. All flight mirror tests are expected to be completed in June 2011. The Webb telescope is scheduled for launch in 2013. Northrop Grumman is the prime contractor for the Webb telescope, leading a design and development team under contract to NASA’s Goddard Space Flight Center.  "It has taken years of intense effort for the Webb Telescope team to begin flight mirror cryotesting and we’re gratified that testing was successful," said Martin Mohan, Webb telescope program manager for Northrop Grumman’s Aerospace Systems sector, Redondo Beach, Calif. "Along the way, we’ve had to invent entire manufacturing and measurement processes because no one has ever built a telescope this large that has to operate at temperatures this extreme." The James Webb Space Telescope is the next-generation premier space observatory, exploring deep space phenomena from distant galaxies to nearby planets and stars. The Webb Telescope will give scientists clues about the formation of the universe and the evolution of our own solar system, from the first light after the Big Bang to the formation of star systems capable of supporting life on planets like Earth.
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 Engineers have successfully ejected the dust cover from NASA's Kepler telescope, a spaceborne mission soon to begin searching for worlds like Earth. "The cover released and flew away exactly as we designed it to do," said Kepler Project Manager James Fanson of NASA's Jet Propulsion Laboratory, Pasadena, Calif. "This is a critical step toward answering a question that has come down to us across 100 generations of human history -- are there other planets like Earth, or are we alone in the galaxy?" Kepler, which launched on March 6 from Cape Canaveral, Fla., will spend three-and-a-half years staring at more than 100,000 stars in our Milky Way galaxy for signs of Earth-size planets. Some of the planets are expected to orbit in a star's "habitable zone," a warm region where water could pool on the surface. The mission's science instrument, called a photometer, contains the largest camera ever flown in space -- its 42 charge-coupled devices ( CCDs) will detect slight dips in starlight, which occur when planets passing in front of their stars partially block the light from Kepler's view. The telescope's oval-shaped dust cover, measuring 1.7 meters by 1.3 meters (67 inches by 52 inches), protected the photometer from contamination before and after launch. The dust cover also blocked stray light from entering the telescope during launch -- light that could have damaged its sensitive detectors. In addition, the cover was important for calibrating the photometer. Images taken in the dark helped characterize noise coming from the instrument's electronics, and this noise will later be removed from the actual science data. "Now the photometer can see the stars and will soon start the task of detecting the planets," said Kepler's Science Principal Investigator William Borucki at N ASA's Ames Research Center, Moffett Field, Calif. "We have thoroughly measured the background noise so that our photometer can detect minute changes in a star's brightness caused by planets." At 7:13 p.m. PDT on April 7, engineers at Kepler's mission operations center at the Laboratory for Atmospheric and Space Physics, Boulder, Colo., sent commands to pass an electrical current through a " burn wire" to break the wire and release a latch holding the cover closed. The spring-loaded cover swung open on a fly-away hinge, before drifting away from the spacecraft. The cover is now in its own orbit around the sun, similar to Kepler's sun-centric orbit. See an animation of the event at http://www.nasa.gov/mission_pages/kepler/multimedia/videos/cover.html . With the cover off, starlight is entering the photometer and being imaged onto its focal plane. Engineers will continue calibrating the instrument using images of stars for another several weeks, after which science observations will begin. Kepler is a NASA Discovery mission. NASA's Ames Research Center Ames is the home organization of the science principal investigator, and is responsible for the ground system development, mission operations and science data analysis. NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Kepler mission development. Ball Aerospace & Technologies Corp., Boulder, Colo., is responsible for developing the Kepler flight system and supporting mission operations. For more information about the Kepler mission, visit http://www.nasa.gov/kepler .
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 Life on Earth is thought to have arisen from a hot soup of chemicals. Does this same soup exist on planets around other stars? A new study from NASA's Spitzer Space Telescope hints that planets around stars cooler than our sun might possess a different mix of potentially life-forming, or " prebiotic," chemicals. Astronomers used Spitzer to look for a prebiotic chemical, called hydrogen cyanide, in the planet-forming material swirling around different types of stars. Hydrogen cyanide is a component of adenine, which is a basic element of DNA. DNA can be found in every living organism on Earth. The researchers detected hydrogen cyanide molecules in disks circling yellow stars like our sun -- but found none around cooler and smaller stars, such as the reddish-colored " M-dwarfs" and " brown dwarfs" common throughout the universe. "Prebiotic chemistry may unfold differently on planets around cool stars," said Ilaria Pascucci, lead author of the new study from Johns Hopkins University, Baltimore, Md. The study will appear in the April 10 issue of the Astrophysical Journal. Young stars are born inside cocoons of dust and gas, which eventually flatten to disks. Dust and gas in the disks provide the raw material from which planets form. Scientists think the molecules making up the primordial ooze of life on Earth might have formed in such a disk. Prebiotic molecules, such as adenine, are thought to have rained down to our young planet via meteorites that crashed on the surface. "It is plausible that life on Earth was kick-started by a rich supply of molecules delivered from space," said Pascucci. Could the same life-generating steps take place around other stars? Pascucci and her colleagues addressed this question by examining the planet-forming disks around 17 cool and 44 sun-like stars using Spitzer's infrared spectrograph, an instrument that breaks light apart, revealing signatures of chemicals. The stars are all about one to three million years old, an age when planets are thought to be growing. The astronomers specifically looked for ratios of hydrogen cyanide to a baseline molecule, acetylene. They found that the cool stars, both the M-dwarf stars and brown dwarfs, showed no hydrogen cyanide at all, while 30 percent of the sun-like stars did. "Perhaps ultraviolet light, which is much stronger around the sun-like stars, may drive a higher production of the hydrogen cyanide," said Pascucci. The team did detect their baseline molecule, acetylene, around the cool stars, demonstrating that the experiment worked. This is the first time that any kind of molecule has been spotted in the disks around cool stars. The findings have implications for planets that have recently been discovered around M-dwarf stars. Some of these planets are thought to be large versions of Earth, the so-called super Earths, but so far none of them are believed to orbit in the habitable zone, where water would be liquid. If such a planet is discovered, could it sustain life? Astronomers aren't sure. M-dwarfs have extreme magnetic outbursts that could be disruptive to developing life. But, with the new Spitzer results, they have another piece of data to consider: these planets might be deficient in hydrogen cyanide, a molecule thought to have eventually become a part of us. Said Douglas Hudgins, the Spitzer program scientist at NASA Headquarters, Washington, "Although scientists have long been aware that the tumultuous nature of many cool stars might present a significant challenge for the development of life, this result begs an even more fundamental question: Do cool star systems even contain the necessary ingredients for the formation of life? If the answer is no then questions about life around cool stars become moot."  Other authors include Daniel Apai of the Space Telescope Science Institute, Baltimore, Md.; Kevin Luhman of Pennsylvania State University, University Park; Thomas Henning and Jeroen Bouwman of the Max Planck Institute for Astronomy, Germany; Michael Meyer of the University of Arizona, Tucson; Fred Lahuis of the SRON Netherlands Institute for Space Research, the Netherlands; and Antonella Natta of the Arcetri Astrophysical Observatory, Italy. NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology, also in Pasadena. Caltech manages JPL for NASA. Spitzer's infrared spectrograph, which made the new observations, was built by Cornell University, Ithaca, N.Y. Its development was led by Jim Houck of Cornell. For more information about Spitzer, visit http://www.spitzer.caltech.edu/spitzer/ and http://www.nasa.gov/spitzer/ .
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 In January 2008, a small Twin Otter airplane outfitted with skis touched down on the icy edge of Antarctica's Pine Island Glacier, carrying NASA glaciologist Robert Bindschadler and a crew of scientists and technicians. It was the first time anyone had landed a plane on this ice shelf floating on the edge of the West Antarctic ice sheet. It will also probably be the last. Bindschadler and colleagues set out to take the first-ever look beneath the ice shelf, which polar scientists believe to be thinning because of warm ocean waters below. But shortly after setting down on the ice, the team discovered the landscape was too rough and the possible runways too short for the multiple takeoffs and landings needed to transport their equipment to the field site. The team constructed a weather station and deployed global positioning system (GPS) units as close to the ice shelf as possible, and headed home. "This expedition is like landing on a different planet," said Bindschadler, a scientist at NASA's Goddard Space Flight Center in Greenbelt, Md. Like astronauts exploring Mars, the researchers have to anticipate and carry everything they need to survive. Satellites, such as the Ice, Cloud and Land Elevation Satellite (ICESat), Terra and Landsat, provide a broad look at Antarctica, but scientists don’t know exactly what the remote environment will look like until they get there. But now they know. And they are going back. In a project that started under the auspices of the International Polar Year ( IPY), Bindschadler and crew are now planning the next steps for research on Pine Island Glacier. They will go back to Antarctica for the 2009-2010 field season to work out the "choreography" required of drilling a 13-centimeter (5-inch) diameter hole though 550 meters (1,800 feet) of ice. The goal is to deploy water-profiling instruments and cameras in the sea below the ice shelf in 2011-2012. It will take two years to turn a section of the remote ice sheet into a " village" for research because transportation and setup of field camps can happen only during the short Antarctic summer (late October though late January). They will need a place to eat, sleep, work, and bathe; a generator for electrical power; a safe location for helicopter landings; and lots of food and fuel. That’s tens of thousands of pounds of equipment. NASA and the National Science Foundation, which is co-funding the expedition, are now planning to fly the equipment about 1,600 kilometers (1,000 miles) from McMurdo Station to Byrd Station, and then slowly drive across the remaining 640 kilometers (400 miles) of snow and ice to Pine Island Glacier. "It's like flying from Washington to Kansas City in an aircraft, and then driving to Denver at lawn-mower speeds," Bindschadler said. When the team returns to the ice shelf in 2010, the logistical operation and dress rehearsals will be over and the real deployment will begin. It will be the first sustained look at how water and ice interact beneath this fragile ice shelf.
NASA's researchers are eager to return so they can understand what is accelerating changes to the ice shelf -- 40 kilometers (25 miles) long and 20 kilometers (12 miles) wide -- which extends from the Pine Island Glacier and floats on the Amundsen Sea. It is the leading edge of one of the two major glaciers that drain the West Antarctic Ice Sheet. Scientists have calculated that ice flowing from the shelf has accelerated from 3.7 to 4.2 kilometers per year (2.3 to 2.6 miles) since Bindschadler's visit just a year ago. “We want to get a sustained look at what's going on under the ice and figure out why the ice shelf is sliding more swiftly into the Amundsen Sea,” Bindschadler said. He believes the acceleration is caused by warm ocean water melting the glacier from below. Warmer waters may be welling up from about 600 to 1,000 meters depth (2,000 to 3,300 feet) and circulating on the continental shelf. This warm ocean water is thinning the base of the ice shelf and gradually reducing the pressure that holds the ice sheet on the continent. Polar scientists are puzzled: where is the warm water coming from and how fast is it moving? Does the upwelling change by season, and exactly how is the ice shelf responding? "We still don't have any consistent, direct measurements in the ocean" Bindschadler said. "Consistent measurements will give us better quantitative handle on how much melting is taking place." Despite the initial setbacks, the science goals for the research expedition have not changed. "If anything, this additional time and extra planning is making us bolder," Bindschadler said. "We're daring to go to where the field challenges may be greater, but where the scientific return is also greater."
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NASA astronaut Mike Massimino is using Twitter to provide a unique, behind the scenes peek at the last weeks of his training for the fifth and final shuttle servicing mission to NASA's Hubble Space Telescope. Massimino, whose Twitter username is Astro_Mike (@Astro_Mike), will fly aboard space shuttle Atlantis as a mission specialist and spacewalker during the STS-125 mission, targeted to launch May 12. Atlantis' 11-day flight will include five spacewalks to refurbish and upgrade Hubble with state-of-the-art science instruments. After the astronaut's visit, Hubble's capabilities will be expanded and its lifetime extended through at least 2014. This will be Massimino's second trip to space. He first flew on the STS-109 mission to Hubble in 2002. During that flight, he performed two spacewalks. Along with Massimino, the crew of Atlantis includes Commander Scott Altman, Pilot Gregory C. Johnson and Mission Specialists Andrew Feustel, Michael Good, John Grunsfeld and Megan McArthur. To follow Massimino's Twitter, visit: http://twitter.com/Astro_Mike Follow NASA mission activities on Twitter @NASA, and for a complete list of all agency missions on Twitter, visit:
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 The latest Arctic sea ice data from NASA and the National Snow and Ice Data Center show that the decade-long trend of shrinking sea ice cover is continuing. New evidence from satellite observations also shows that the ice cap is thinning as well. Arctic sea ice works like an air conditioner for the global climate system. Ice naturally cools air and water masses, plays a key role in ocean circulation, and reflects solar radiation back into space. In recent years, Arctic sea ice has been declining at a surprising rate. Scientists who track Arctic sea ice cover from space announced today that this winter had the fifth lowest maximum ice extent on record. The six lowest maximum events since satellite monitoring began in 1979 have all occurred in the past six years (2004-2009). Until recently, the majority of Arctic sea ice survived at least one summer and often several. But things have changed dramatically, according to a team of University of Colorado, Boulder, scientists led by Charles Fowler. Thin seasonal ice -- ice that melts and re-freezes every year -- makes up about 70 percent of the Arctic sea ice in wintertime, up from 40 to 50 percent in the 1980s and 1990s. Thicker ice, which survives two or more years, now comprises just 10 percent of wintertime ice cover, down from 30 to 40 percent. According to researchers from the National Snow and Ice Data Center in Boulder, Colo., the maximum sea ice extent for 2008-09, reached on Feb. 28, was 5.85 million square miles. That is 278,000 square miles less than the average extent for 1979 to 2000. "Ice extent is an important measure of the health of the Arctic, but it only gives us a two-dimensional view of the ice cover," said Walter Meier, research scientist at the center and the University of Colorado, Boulder. "Thickness is important, especially in the winter, because it is the best overall indicator of the health of the ice cover. As the ice cover in the Arctic grows thinner, it grows more vulnerable to melting in the summer."  The Arctic ice cap grows each winter as the sun sets for several months and intense cold sets in. Some of that ice is naturally pushed out of the Arctic by winds, while much of it melts in place during summer. The thicker, older ice that survives one or more summers is more likely to persist through the next summer. Sea ice thickness has been hard to measure directly, so scientists have typically used estimates of ice age to approximate its thickness. But last year a team of researchers led by Ron Kwok of NASA's Jet Propulsion Laboratory in Pasadena, Calif., produced the first map of sea ice thickness over the entire Arctic basin. Using two years of data from NASA's Ice, Cloud, and land Elevation Satellite ( ICESat), Kwok's team estimated thickness and volume of the Arctic Ocean ice cover for 2005 and 2006. They found that the average winter volume of Arctic sea ice contained enough water to fill Lake Michigan and Lake Superior combined.  The older, thicker sea ice is declining and is being replaced with newer, thinner ice that is more vulnerable to summer melt, according to Kwok. His team found that seasonal sea ice averages about 6 feet in thickness, while ice that had lasted through more than one summer averages about 9 feet, though it can grow much thicker in some locations near the coast. Kwok is currently working to extend the ICESat estimate further, from 2003 to 2008, to see how the recent decline in the area covered by sea ice is mirrored in changes in its volume. "With these new data on both the area and thickness of Arctic sea ice, we will be able to better understand the sensitivity and vulnerability of the ice cover to changes in climate," Kwok said.
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NASA Television will air the landing of the Expedition 18 crew and a visiting spaceflight participant on Wednesday, April 8. Russian managers on Friday postponed the Soyuz landing one day and switched to a more southerly landing site in Kazakhstan because of soggy conditions at the original site. Expedition 18 Commander E. Michael Fincke, Flight Engineer and Soyuz Commander Yury Lonchakov and Spaceflight Participant Charles Simonyi will return to Earth at 2:15 a.m. CDT, which is 1:15 p.m. local time in Kazakhstan. The landing will take place near the town of Dzhezkazgan, which is west of Karaganda and southeast of the usual landing zone near Arkalyk. Fincke and Lonchakov have been aboard the orbiting laboratory since October 2008 and will land in the Soyuz TMA-13 spacecraft that carried them into orbit. Upcoming NASA TV Soyuz landing programming events (all times CDT): April 7, Tuesday 7:30 p.m. -- Coverage of the crew's farewell and hatch closure 10:30 p.m. -- Coverage of the undocking of Soyuz TMA-13 from the International Space Station April 8, Wednesday 1 a.m. -- Coverage of the deorbit burn and landing of Soyuz TMA-13 (deorbit burn at 1:24 a.m.; landing at 2:15 a.m.) 12:30 p.m. – Video File feed of landing site activities and the crew's welcoming ceremony in Kazakhstan 2 p.m. -- Video File feed of the crew's return to Star City, Russia and a post-landing interview with Expedition 18 Commander Mike Fincke. For NASA TV streaming video, downlink and schedule information, visit: http://www.nasa.gov/ntv http://www.nasa.gov/station
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NASA and Lockheed Martin's Student Signatures in Space (S3) program will be one of the highlighted projects during this year's Space Day, celebrated annually on the first Friday in May. The mission of Space Day is to use space-related activities to inspire and prepare young people for careers in science, technology, engineering and mathematics. Student Signatures in Space began in 1997 as a way to draw kids into space studies by giving them a personal connection to space. Participating schools are sent large posters for students to sign on Space Day. NASA and Lockheed Martin, of Bethesda, Md., are currently accepting school names for participation. The program is open to elementary, middle, and high schools, as well as science museums and regional Boy Scout and Girl Scout councils. After schools return the posters to Lockheed Martin, the signatures are scanned onto a disk and flown aboard a space shuttle mission. Schools also receive lesson plans and information about the mission their signed posters are flying on. Upon completion of the shuttle flight, the posters are returned to the schools along with a photo of the astronaut crew that took the signatures to space and a NASA flight certification verifying that the signatures flew in space. Schools are allowed to participate in the signatures program once every six years. The project is free to participants. Program partners cover all program costs, including shipping expenses for return of the signed posters. Schools and other organizations may request a sign-up form by e-mailing S3 Program Manager April Tensen at signatures@mindspring.comStudent Signatures in Space is limited to 500 schools per year, and schools are registered on a first-come, first-served basis. Schools that sign up after the maximum capacity is reached will be put on a list to participate in the following year's program. For information on Space Day or Student Signatures in Space, visit: http://www.spaceday.org For information about NASA education programs, visit:
http://www.nasa.gov/education
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 Why does Fargo flood? The Red River of the North, which forms the border between North Dakota and Minnesota, has a long history of severe floods. Major floods include those of 1826, 1897, 1950, 1997, and now 2009. The 1997 flood caused billions of dollars of damage, with greatest impact to the city of Grand Forks, north of and downstream from Fargo. The 2009 flood, which has primarily impacted Fargo, appears to have peaked early on March 28. Several factors combine to cause floods. Obviously, rainfall and snowmelt rates (and their geographic distribution) are the fundamental variables that create flooding in some years and not others. But the repetition of flooding in Fargo (and areas downstream), rather than in adjacent regions, can be attributed largely to its topographic setting and geologic history. The formation of landforms in the geologic past is often interpretable from digital topographic data, such as that supplied by the Shuttle Radar Topography Mission (SRTM). This image, covering parts of North Dakota, Minnesota, and South Dakota, displays ground elevation as brightness (higher is brighter) plus has simulated shading (with illumination from the north) to enhance topographic detail such as stream channels, ridges, and cliffs. The Red River of the North is the only major river that flows northward from the United States into Canada. In this scene it flows almost straight north from Fargo. North of this image it continues past the city of Winnipeg, Manitoba, and into Lake Winnipeg, which in turn drains to Hudson Bay. In the United States, the river lies in a trough that was shaped by continental glaciers that pushed south from Canada during the Pleistocene epoch, up to about 10,000 years ago. This trough is about 70 km (45 miles) wide and tens of meters (very generally about 100 feet) deep. Here near Fargo it lies on the east side of a much broader, topographically distinct pathway of former glaciation that narrows to about 190 km (120 miles) wide. South of Fargo this narrowed pathway splits into two distinct paths (broad dark swaths on the image) that were carved by the southward flowing glaciers. Arcuate glacial moraines (deposits of rocks that were carried by glaciers) can be seen near this split, near what is now the approximate boundary between the Hudson Bay and Gulf of Mexico drainage basins (the latter via the Mississippi River). This glacial landscape has features that were favorable for the transport of ice but are not now so favorable for the transport of water. As measured in the digital elevation data, the Red River decreases in elevation only 40 meters (130 feet) from Fargo to the Canadian border (top of image) over a straight-line distance of 235 kilometers (145 miles) along the glacial trough. This is a gradient of only 17 centimeters per kilometer (11 inches per mile), and the actual river gradient is much lower as it follows a longer curvilinear path. Areas surrounding the trough (more rugged and bright in the image) have variable but generally much steeper gradients. In simple terms, this is a fundamental cause of flooding in Fargo. The speed of drainage of the rainfall and snowmelt is greatly related to topographic slope. The steeper slopes and merging streams concentrate water runoff into the glacial trough at Fargo, while the lower gradients within the trough allow the water to spread (and flood) but not drain quickly away. Elevation data used in this image were acquired by the Shuttle Radar Topography Mission aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. The mission was a cooperative project between NASA, the National Geospatial-Intelligence Agency (NGA) of the U.S. Department of Defense, and the German and Italian space agencies, and was managed by NASA's Jet Propulsion Laboratory, Pasadena, California.
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While touring the Saturn system in 2008, Cassini enabled great scientific studies and observations. Below is captured the Top 10 Science Highlights of the year as selected by the science teams. - Identification of liquid ethane in a lake on Titan
- Polar storms on Saturn
- Strong inference of a liquid water layer in Titan's interior
- The likelihood of dusty rings around Rhea
- The possibility of plate-tectonic-like spreading in the Enceladus south polar region
- Water vapor jets inside the plume of gas leaving Enceladus
- Moonlet population in and around the F ring
- New insights into Saturn's aurora
- Three belts of sub-moonlets in the A ring (propellers)
- Six month-old lightning storm shatters record for longevity
1) Identification of liquid ethane in a lake on Titan NASA scientists have concluded that at least one of the large lakes observed on Saturn's moon Titan contains liquid hydrocarbons, and have positively identified the presence of ethane. This makes Titan the only body in our solar system beyond Earth known to have liquid on its surface. Scientists made the measurements using data from an instrument aboard the Cassini spacecraft. The instrument identified chemically different materials based on the way they absorb and reflect infrared light. Before Cassini, scientists thought Titan would have global oceans of methane, ethane and other light hydrocarbons. More than 40 close flybys of Titan by Cassini show no such global oceans exist, but hundreds of dark, lake-like features are present. Until now, it was not known whether these features were liquid or simply dark, solid material. Also see:
NASA Confirms Liquid Lake on Saturn Moon Cassini Finds Hydrocarbon Rains May Fill Titan Lakes
2) Polar storms on Saturn Cassini scientists revisited the north polar hexagon last year. This huge polygonal pattern in the clouds was first seen by Voyager in 1980. In 2008, Cassini found that the aurora glows at infrared wavelengths at the same latitude as the hexagon, suggesting a connection over a huge range of altitudes.
In addition, Cassini found a hot spot resembling the eye of a hurricane, but it is locked to the north pole at the center of the hexagon, with swirling cyclonic winds signifying a low pressure center. The hot spot is confined to latitudes above 88 degrees, while the corners of the hexagon are at 75 degrees. The north polar hot spot resembles one in the south that was imaged in exquisite detail in 2008 These findings cast light on how large vortices - swirling masses of gas - behave in planetary atmospheres throughout the solar system. The new-found cyclone at Saturn’s north pole is only visible in the near-infrared wavelengths because the north pole is in winter, thus in darkness to visible-light cameras. At these wavelengths, about seven times greater than light seen by the human eye, the clouds deep inside Saturn’s atmosphere are seen in silhouette against the background glow of Saturn’s internal heat. Peak winds exceed 450 kilometers per hour (280 mph, or 130 m/s) near 88 degrees latitude. New measurements by Cassini show that clouds within the hexagonal feature located near 77 degrees north latitude zoom around the “race track” of the hexagon at this same high speed -- 460 kilometers per hour (127 meters per second, or 285 mph) -- while the hexagonal “race track” itself stays nearly stationary in Saturn’s atmosphere.
3) Strong inference of a liquid water layer in Titan's interior NASA's Cassini spacecraft has found evidence that points to the existence of an underground ocean of water and ammonia on Saturn's moon Titan. The findings, made using radar measurements of Titan's rotation, appeared in the March 21 issue of the journal Science. "With its organic dunes, lakes, channels and mountains, Titan has one of the most varied, active and Earth-like surfaces in the solar system," said Ralph Lorenz, lead author of the paper and Cassini radar scientist at the Johns Hopkins Applied Physics Laboratory in Laurel, Md., "Now we see changes in the way Titan rotates, giving us a window into Titan's interior beneath the surface." Subsequent data has suggested that these radar observations may be related to precession, only indirectly related to the presence of an ocean, but other geophysical evidence continues to point to a subsurface ocean. Titan continues to amaze and confound!
4) The likelihood of dusty rings around Rhea NASA's Cassini spacecraft has found evidence of material orbiting Rhea, Saturn's second largest moon. This is the first time rings may have been found around a moon. A broad debris disk and at least one ring appear to have been detected by a suite of six instruments on Cassini specifically designed to study the atmospheres and particles around Saturn and its moons.
5) The possibility of plate-tectonic-like spreading in the Enceladus south polar region The closer scientists look at Saturn's small moon Enceladus, the more they find evidence of an active world. The most recent flybys of Enceladus made by NASA's Cassini spacecraft have provided new signs of ongoing changes on and around the moon. The latest high-resolution images of Enceladus show signs that the south polar surface changes over time. Close views of the southern polar region, where jets of water vapor and icy particles spew from vents within the moon's distinctive "tiger stripe" fractures, provide surprising evidence of Earth-like tectonics. They yield new insight into what may be happening within the fractures. The latest data on the plume -- the huge cloud of vapor and particles fed by the jets that extend into space -- show it varies over time and has a far-reaching effect on Saturn's magnetosphere.
6) Water vapor jets inside the plume of gas leaving Enceladus Scientists continue to search for the cause of the geysers on Saturn's moon Enceladus. The geysers are visible as a large plume of water vapor and ice particles escaping the moon. Inside the plume are jets of dust and gas. What causes and controls the jets is a mystery. The Cassini spacecraft continues to collect new data to look for clues. At the heart of the search is the question of whether the jets originate from an underground source of liquid water. Some scientists working on the Cosmic Dust Analyzer (CDA) have suggested that the sodium found present in the E ring can be traced back to liquid in Enceladus. Some other theories offer models where the jets could be caused by mechanisms that do not require liquid water. Painstaking detective work by Cassini scientists is testing the possibilities to get closer to an answer.
7) Moonlet population in and around the F ring A team of scientists led from the UK has found that the rapid changes in Saturn's F ring can be attributed to small moonlets causing perturbations. Their results are reported in Nature (June 5, 2008). Saturn's F ring has long been of interest to scientists as its features change on timescales from hours to years and it is probably the only location in the solar system where large scale collisions happen on a daily basis. Understanding these processes helps scientists understand the early stages of planet formation. Models have been developed which clearly imply a population of perhaps hundreds of unseen objects with sizes between 100 meters and 1 kilometer or so, both lying within and also criss-crossing through the narrow F ring core and causing havoc in the orbits of its particles. Stellar occultations also found a number of clumps and opaque objects, measuring their size directly to be in the few hundred meter size range.
8) New insights into Saturn's aurora Saturn has its own unique brand of aurora that lights up the polar cap, unlike any other planetary aurora known in our solar system. This odd phenomenon revealed itself to one of the infrared instruments on NASA's Cassini spacecraft. Also see:
Cassini Finds Mysterious New Aurora on Saturn
9) Three belts of sub-moonlets in the A ring (propellers) A new comprehensive study established the existence and orbital properties of an order of magnitude more objects of 100-300 metersacross buried in the rings than previously known. These objects have been dubbed "propellors" because of the shape of the surrounding material they disturb. The greatly improved statistics revealed that these large objects occupy three distinct belts in the A ring, which correlate with nearby resonances or gaps in no obvious way. No evidence for such objects has been found in other rings. It remains unknown if the objects are primordial "shards" or locally grown, but it is now clear that the mass in this population is much smaller than in the visible ring particles themselves.
10) Six month-old lightning storm shatters record for longevity Two instruments on Cassini regularly team up to monitor lightning storms in Saturn's atmosphere. The RPWS detects radio pulses from the electrical discharges, and the ISS images the storms. The RPWS only detects the electrical discharges when the storm is on the side of Saturn facing the spacecraft or just over the horizon on the night side. Often a year goes by when there are no discharges, during which time the ISS does not see the storms. Then suddenly the radio signals begin and a new storm appears in the atmosphere. One such storm was identified on November 27, 2007, probably within a day of its birth. Unlike past storms, which lasted for a few weeks at best, this one lasted for 7.5 months and thereby set a new record for longevity of lightning storms throughout the solar system.
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 The sunspot cycle is behaving a little like the stock market. Just when you think it has hit bottom, it goes even lower. 2008 was a bear. There were no sunspots observed on 266 of the year's 366 days (73 percent). To find a year with more blank suns, you have to go all the way back to 1913, which had 311 spotless days. Prompted by these numbers, some observers suggested that the solar cycle had hit bottom in 2008. Maybe not. Sunspot counts for 2009 have dropped even lower. As of March 31st, there were no sunspots on 78 of the year's 90 days (87 percent). It adds up to one inescapable conclusion: "We're experiencing a very deep solar minimum," says solar physicist Dean Pesnell of NASA’s Goddard Space Flight Center in Greenbelt, Md. "This is the quietest sun we've seen in almost a century," agrees forecaster David Hathaway of NASA’s Marshall Space Flight Center in Huntsville, Ala. Quiet suns come along every 11 years or so. It's a natural part of the sunspot cycle, discovered by German astronomer Heinrich Schwabe in the mid-1800s. Sunspots are planet-sized islands of magnetism on the surface of the sun, and they are sources of solar flares, coronal mass ejections, and intense UV radiation. Plotting sunspot counts, Schwabe saw that peaks of solar activity were always followed by valleys of relative calm—a clockwork pattern that has held true for more than 200 years. The current solar minimum is part of that pattern. In fact, it's right on time. But is it supposed to be this quiet? Measurements by the Ulysses spacecraft reveal a 20 percent drop in solar wind pressure since the mid-1990s—the lowest point since such measurements began in the 1960s. The solar wind helps keep galactic cosmic rays out of the inner solar system. With the solar wind flagging, more cosmic rays penetrate the solar system, resulting in increased health hazards for astronauts. Weaker solar wind also means fewer geomagnetic storms and auroras on Earth. Careful measurements by several NASA spacecraft have also shown that the sun's brightness has dimmed by 0.02 percent at visible wavelengths and a whopping 6 percent at extreme UV wavelengths since the solar minimum of 1996. These changes are not enough to reverse global warming, but there are some other, noticeable side-effects. Earth's upper atmosphere is heated less by the sun and it is therefore less "puffed up." Satellites in Earth orbit experience less atmospheric drag, extending their operational lifetimes. That’s the good news. Unfortunately, space junk also remains in orbit longer, posing an increased threat to useful satellites. Finally, radio telescopes are recording the dimmest " radio sun" since 1955. After World War II, astronomers began keeping records of the sun's brightness at radio wavelengths, particularly 10.7 cm. Some researchers believe that the lessening of radio emissions during this solar minimum is an indication of weakness in the sun's global magnetic field. No one is certain, however, because the source of these long-monitored radio emissions is not fully understood. All these lows have sparked a debate about whether the ongoing minimum is extreme or just an overdue market correction following a string of unusually intense solar maxima. "Since the Space Age began in the 1950s, solar activity has been generally high," notes Hathaway. "Five of the ten most intense solar cycles on record have occurred in the last 50 years. We're just not used to this kind of deep calm." Deep calm was fairly common a hundred years ago. The solar minima of 1901 and 1913, for instance, were even longer than what we're experiencing now. To match those minima in depth and longevity, the current minimum will have to last at least another year. In a way, the calm is exciting, says Pesnell. "For the first time in history, we're getting to observe a deep solar minimum." A fleet of spacecraft — including the Solar and Heliospheric Observatory ( SOHO), the twin probes of the Solar Terrestrial Relations Observatory (STEREO), and several other satellites — are all studying the sun and its effects on Earth. Using technology that didn't exist 100 years ago, scientists are measuring solar winds, cosmic rays, irradiance and magnetic fields and finding that solar minimum is much more interesting than anyone expected. Modern technology cannot, however, predict what comes next. Competing models by dozens of solar physicists disagree, sometimes sharply, on when this solar minimum will end and how big the next solar maximum will be. The great uncertainty stems from one simple fact: No one fully understands the underlying physics of the sunspot cycle. Pesnell believes sunspot counts should pick up again soon, "possibly by the end of the year," to be followed by a solar maximum of below-average intensity in 2012 or 2013. But like other forecasters, he knows he could be wrong. Bull or bear? Stay tuned for updates.
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 A powerful, newly refined image-processing technique may allow astronomers to discover extrasolar planets that are possibly lurking in over a decade's worth of Hubble Space Telescope archival data. David Lafrenière of the University of Toronto, Ontario, Canada, has successfully demonstrated this new strategy for planet hunting by identifying an exoplanet that went undetected in Hubble images taken in 1998 with its Near Infrared Camera and Multi-Object Spectrometer ( NICMOS). In addition to illustrating the power of new data-processing techniques, this finding underscores the value of the Hubble data archive, on which those new techniques can be used. The planet, estimated to be at least seven times Jupiter's mass, was originally discovered in images taken with the Keck and Gemini North telescopes in 2007 and 2008. It is the outermost of three massive planets known to orbit the dusty young star HR 8799, which is 130 light-years away. NICMOS could not see the other two planets because its coronagraphic spot -- a device which blots out the glare of the star -- also interferes with observing the two inner planets. "We've shown that NICMOS is more powerful than previously thought for imaging planets," says Lafrenière. "Our new image-processing technique efficiently subtracts the glare from a star that spills over the coronagraph's edge, allowing us to see planets that are one-tenth the brightness of what could be detected before with Hubble." Lafrenière adapted an image reconstruction technique that was first developed for ground-based observatories. Using the new technique, he recovered the planet in NICMOS observations taken 10 years before the Keck/Gemini discovery. The Hubble picture not only provides important confirmation of the planet's existence, it provides a longer baseline for demonstrating that the object is in an orbit about the star. "To get a good determination of the orbit we have to wait a very long time because the planet is moving so slowly ( it has a 400-year period)," says Lafrenière. "The 10-year-old Hubble data take us that much closer to having a precise measure of the orbit." NICMOS's view provided new insights into the physical characteristics of the planet, too. This was possible because NICMOS works at near-infrared wavelengths that are severely blocked by Earth's atmosphere due to absorption by water vapor.
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 A collection of NASA missions will be involved in a live event Friday, April 3, that will allow the public to get an inside look at how these missions are run. " Around the World in 80 Telescopes" is a 24-hour webcast that is part of the "100 Hours of Astronomy" event for the International Year of Astronomy 2009. During the webcast, viewers will be able to visit some of the most advanced telescopes on and off the planet. For NASA's space-based missions, the webcast will be broadcast from control centers throughout the United States. To view the webcast, visit http://www.100hoursofastronomy.org/component/content/article/34/75 . As part of the webcast, most of the missions will release a never-before-seen image from the telescope or observatory. The new images can be found on the Web sites listed below. Please note these times correspond to the beginning of each mission's segment on the live webcast and when each new image will be available. The NASA missions participating in the webcast, in chronological order, are (times are Pacific Daylight Time, April 3): Hubble Space Telescope: 10:20 a.m. http://hubblesite.org/news/2009/14Swift Gamma-ray Burst Explorer: 10:40 a.m. http://www.nasa.gov/swiftFermi Gamma-ray Space Telescope: 11 a.m. http://www.nasa.gov/fermiSOHO and TRACE: 12:20 p.m. http://sohowww.nascom.nasa.gov/ and http://sunland.gsfc.nasa.gov/smex/trace/STEREO: 12:40 p.m. http://stereo.gsfc.nasa.gov/Galaxy Evolution Explorer: 1:20 p.m. http://www.galex.caltech.edu/ and www.nasa.gov/galexChandra X-ray Observatory: 1:40 p.m. http://www.chandra.harvard.edu/photo/2009Spitzer Space Telescope: 2:20 p.m. http://www.spitzer.caltech.edu/spitzer/index.shtml and www.nasa.gov/spitzerKepler: 12:05 a.m. (April 4) http://kepler.nasa.govFor information about the International Year of Astronomy, visit http://astronomy2009.nasa.gov/ . For more information about NASA and agency programs, visit http://www.nasa.gov . NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology, also in Pasadena. Caltech manages JPL for NASA. Graphics and more information about Spitzer are online at http://www.spitzer.caltech.edu/spitzer and http://www.nasa.gov/spitzer . Caltech leads the Galaxy Evolution Explorer mission and is responsible for science operations and data analysis. JPL manages the mission and built the science instrument. The mission was developed under NASA's Explorers Program managed by the Goddard Space Flight Center, Greenbelt, Md. Researchers sponsored by Yonsei University in South Korea and the Centre National d'Etudes Spatiales ( CNES) in France collaborated on this mission. Graphics and additional information about the Galaxy Evolution Explorer is online at http://www.galex.caltech.edu and http://www.nasa.gov/galex/ .
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NASA Inspector General Robert Cobb submitted a letter of resignation to the White House on Thursday, April 2, 2009. President Barack Obama accepted Cobb's resignation, which is effective April 11. The text of the letter is: Dear Mr. President: With this letter I tender my resignation as the Inspector General of the National Aeronautics and Space Administration, effective April 11, 2009. I have been honored to serve the United States over the past seventeen years, first at the Office of Government Ethics, then at the White House, and for the last seven years as Inspector General. A new Inspector General will find an organization with extraordinarily talented employees dedicated to rooting out fraud, waste, and abuse and promoting the economy, efficiency, and effectiveness of NASA. At NASA, the seemingly impossible is turned into marvels of human achievement. Challenges facing NASA are many, but I am confident that they will be ably met by your Administration, working with NASA's gifted scientists, engineers, institutional leaders, and contractor workforce. I wish you every success. Very Respectfully, Robert W. Cobb
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 The gamma-ray sky comes alive in a movie made from data acquired by NASA’s Fermi Gamma-ray Space Telescope during its first three months of operations. Gamma rays from sources near and far turn the sky into a hypnotic froth. The sun arcs serenely across the northern sky as active galaxies called blazars flare up and fade out. The movie, made from the first 87 days of data from Fermi’s Large Area Telescope (LAT), was revealed today during a live 24-hour video webcast called “ Around the World in 80 Telescopes.” Organized by the European Southern Observatory headquartered in Garching, Germany, the webcast is part of the 100 Hours of Astronomy project, a worldwide celebration of astronomy running through April 5. “The movie shows counts of gamma rays seen by Fermi’s LAT, and each frame shows the gamma rays collected in one day,” said presenter Elizabeth Hays, an astrophysicist on the Fermi team. Only gamma rays with energies greater than 300 million electron volts -- or 150 million times more than that of visible light -- are shown. Brighter colors indicate greater numbers of detected gamma rays and thus the locations of bright gamma-ray sources. The movie shows the entire sky as northern and southern halves, with the plane of our galaxy, the Milky Way, running along the circular edges. “This presentation provides a better view of sources outside our galaxy,” Hays noted, “but it’s an unusual way to view the sky.” The northern view includes the familiar constellation Ursa Major, part of which forms the Big Dipper. The southern view includes the constellations Cetus and Pegasus. “One of the first things to notice in the movie is the source that arcs across the northern galactic sky. That’s the sun moving along the ecliptic plane,” Hays said. The sun appears to move through the sky because the Earth revolves around it. This is the same reason constellations progress through the sky during the year. However, Fermi’s LAT isn’t detecting gamma rays produced directly by the sun -- at least not yet. “The LAT sees the sun because cosmic rays -- nuclei traveling close to the speed of light -- strike the sun’s gas and the light it emits. These collisions produce gamma rays,” Hays explained. The LAT will sense the sun directly when a sufficiently powerful solar eruption occurs, but the sun is now in a quiet portion of its activity cycle. Another striking aspect of the movie is that, even far from the brightest gamma-ray sources, the sky is not dark. “We see a general background of gamma rays over the whole sky,” Hays said. Some of this glow is the result of cosmic rays colliding with gas and light in our own galaxy and producing gamma rays. But some of this emission originates from beyond our galaxy. “Although we don't know exactly where all of these gamma rays are coming from, we know that some of them must be the collective radiation from galaxies we are not detecting directly,” she explained. It’s possible that something more exotic could also be contributing to this background glow, and Fermi is making measurements to test such ideas. One galactic source lies far enough from the Milky Way’s plane that it stands out in the movie. “That’s PSR J1836+5925, one of the new class of pulsars discovered by Fermi,” Hays said. The pulsar is a fast-spinning neutron star that sends a broad fan of gamma rays toward us with each rotation. Neutron stars pack twice the mass of the sun into a sphere the size of Manhattan and can spin thousands of times in one second. “It looks steady in the movie because we have to add up gamma rays from many rotations to see the pulses,” she noted. Most of the other bright sources in the movie are actually distant galaxies. Each of these active galaxies, called blazars, hosts a central black hole with a mass of a million suns. Somehow, the black hole produces extremely fast-moving jets of matter, and with blazars we’re looking almost directly down the jet. “The strong variations in brightness that you see during the movie tell us that something about these jets has changed,” Hays said. One example is the blazar AO 0235+164, located 7.5 billion light-years away in the constellation Aries. “The flares we are seeing happened when the universe was about half of its current age,” she explained. “The LAT sees a very strong flare. The gamma rays increase by 30 to 40 times in a single day. On that day, AO 0235 became one of the brightest gamma-ray sources in the sky.” Fermi’s LAT became the first gamma-ray telescope to see the blazar called PKS 1502+106. The galaxy, located 10 billion light-years away in the constellation Boötes, appeared suddenly, flared in brightness for a few days, and then faded away. Such rapid and dramatic change underscores one of the most valuable things the Fermi team does. “We watch the sky all the time and alert other telescopes, in space and on the ground, when something interesting is going on,” Hays said. This gives other astronomers the chance to watch these events at other wavelengths, such as visible light, infrared, radio, ultraviolet, X-ray, and even gamma rays above the energy the LAT can detect. “The broader the wavelength coverage, the better our understanding of the event will be,” Hays adds. “We have to be quick to catch these flares before they fade away.”
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 On April 1-2, the Hubble Space Telescope photographed the winning target in the Space Telescope Science Institute’s “ You Decide” competition in celebration of the International Year of Astronomy ( IYA). The winner is a group of galaxies called Arp 274. The striking object received 67,021 votes out of the nearly 140,000 votes cast for the six candidate targets. Arp 274, also known as NGC 5679, is a system of three galaxies that appear to be partially overlapping in the image, although they may be at somewhat different distances. The spiral shapes of two of these galaxies appear mostly intact. The third galaxy (to the far left) is more compact, but shows evidence of star formation. Two of the three galaxies are forming new stars at a high rate. This is evident in the bright blue knots of star formation that are strung along the arms of the galaxy on the right and along the small galaxy on the left. The largest component is located in the middle of the three. It appears as a spiral galaxy, which may be barred. The entire system resides at about 400 million light-years away from Earth in the constellation Virgo. Hubble’s Wide Field Planetary Camera 2 was used to image Arp 274. Blue, visible, and infrared filters were combined with a filter that isolates hydrogen emission. The colors in this image reflect the intrinsic color of the different stellar populations that make up the galaxies. Yellowish older stars can be seen in the central bulge of each galaxy. A bright central cluster of stars pinpoint each nucleus. Younger blue stars trace the spiral arms, along with pinkish nebulae that are illuminated by new star formation. Interstellar dust is silhouetted against the starry population. A pair of foreground stars inside our own Milky Way are at far right. The International Year of Astronomy is the celebration of the 400th anniversary of Galileo’s first observations with a telescope. People around the world are coming together to participate in the IYA’s 100 Hours of Astronomy, April 2 to 5. This global astronomy event is geared toward encouraging as many people as possible to experience the night sky. The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency (ESA) and is managed by NASA's Goddard Space Flight Center (GSFC) in Greenbelt, Md. The Space Telescope Science Institute ( STScI) conducts Hubble science operations. The institute is operated for NASA by the Association of Universities for Research in Astronomy, Inc., Washington, D.C.
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NASA's Swift satellite and an international team of astronomers have found a gamma-ray burst from a star that died when the universe was only 630 million years old, or less than five percent of its present age. The event, dubbed GRB 090423, is the most distant cosmic explosion ever seen.
At the same time, Fox led an effort to obtain infrared images of the afterglow using the Gemini North Telescope on Mauna Kea. The source appeared in longer-wavelength images but was absent in an image taken at the shortest wavelength of 1 micron. This "drop out" corresponded to a distance of about 13 billion light-years.
A few hours later, Tanvir's team confirmed the distance using one of the European Very Large Telescopes on Cerro Paranal in Chile.
