NASA's Spitzer Space Telescope captured this image of
comet Holmes in March 2008, five months after the comet suddenly erupted and brightened a millionfold overnight.
Every six years, comet 17P/Holmes speeds away from
Jupiter and heads inward toward the
sun, traveling the same route typically without incident. However, twice in the last 116 years, in November 1892 and October 2007, comet Holmes mysteriously exploded as it approached the
asteroid belt.
This overhead view is of
Atlantis atop a modified 747 as the craft flew over California's high desert. Atlantis and the crew of the
STS-125 mission landed at Edwards Air Force Base on May 24, 2009, and departed Edwards on the journey home via ferry to the
Kennedy Space Center in Florida on Monday, June 1, 2009. The shuttle landed safely the following day at 6:53 p.m. EDT.
Why are many large craters on
Mercury relatively smooth inside? Images from the
MESSENGER spacecraft that flew by
Mercury in October 2008 show previously uncharted regions of the
planet that have large craters with an internal smoothness similar to
Earth's own moon, and are thought to have been flooded by lava floes that are old but not as old as the surrounding more highly cratered surface.
MESSENGER will buzz past
Mercury late in 2009 before entering orbit in 2011.
This
artist's concept shows the smallest star known to host a planet. The
planet, called VB 10b, was discovered using
astrometry, a method in which the wobble induced by a planet on its star is measured precisely on the sky.
The dim, red star, called VB 10, is a so-called
M-dwarf, located 20 light-years away in the constellation Aquila. It has only one-twelfth the mass, and one-tenth the size, of our sun. The planet is a gas giant similar in size to Jupiter but with six times the mass. Though the planet is less massive than its star, the two orbs would have a similar diameter.
VB 10b orbits its
star about every 9 months at a distance of 30 million miles.
This composite image shows a small region of the Chandra Deep Field North. The diffuse blue object near the center of the image is believed to be a cosmic '
ghost' generated by a huge eruption from a
supermassive black hole in a distant galaxy. This X-ray ghost, a.k.a.
HDF 130, remains after powerful radio waves from particles traveling away from the black hole at almost the speed of light, have died off.
HDF 130 is more than 10 billion light years away and existed at a time 3 billion years after the Big Bang, when
galaxies and black holes were forming at a high rate. Near the center of the X-ray ghost is a radio point source indicating the presence of a growing
supermassive black hole.
The image was acquired by ASTER on Oct. 12, 2004. With its 14 spectral bands from the visible to the thermal infrared wavelength region and its high spatial resolution of about 50 to 300 feet, ASTER images Earth to map and monitor the changing surface of our planet and is one of five Earth-observing instruments launched Dec. 18, 1999, on NASA's Terra satellite.
