NASA Releases Images Of Man-Made Crater On Comet
PASADENA, Calif. -- NASA's Stardust spacecraft returned new images of a comet showing a scar resulting from the 2005 Deep Impact mission. The images also showed the comet has a fragile and weak nucleus.The spacecraft made its closest approach to comet Tempel 1 on Monday, Feb. 14, at 8:40 p.m. PST at a distance of approximately 111 miles. Stardust took 72 high-resolution images of the comet. It also accumulated 468 kilobytes of data about the dust in its coma, the cloud that is a comet's atmosphere. The craft is on its second mission of exploration called Stardust-NExT, having completed its prime mission collecting cometary particles and returning them to Earth in 2006.
The Stardust-NExT mission met its goals which included observing
surface features that changed in areas previously seen during the
2005 Deep Impact mission; imaging new terrain; and viewing the crater
generated when the 2005 mission propelled an impactor at the comet.
"This mission is 100 percent successful," said Joe Veverka,
Stardust-NExT principal investigator of Cornell University, Ithaca,
N.Y. "We saw a lot of new things that we didn't expect, and we'll be
working hard to figure out what Tempel 1 is trying to tell us."
Several of the images provide tantalizing clues to the result of the
Deep Impact mission's collision with Tempel 1.
"We see a crater with a small mound in the center, and it appears that
some of the ejecta went up and came right back down," said Pete
Schultz of Brown University, Providence, R.I. "This tells us this
cometary nucleus is fragile and weak based on how subdued the crater
is we see today."
Engineering telemetry downlinked after closest approach indicates the
spacecraft flew through waves of disintegrating cometary particles
including a dozen impacts that penetrated more than one layer of its
protective shielding.
"The data indicate Stardust went through something similar to a B-17
bomber flying through flak in World War II," said Don Brownlee,
Stardust-NExT co-investigator from the University of Washington in
Seattle. "Instead of having a little stream of uniform particles
coming out, they apparently came out in chunks and crumbled."
While the Valentine's Day night encounter of Tempel 1 is complete, the
spacecraft will continue to look at its latest cometary obsession from afar.
"This spacecraft has logged over 3.5 billion miles since launch, and
while its last close encounter is complete, its mission of discovery
is not," said Tim Larson, Stardust-NExT project manager at JPL.
"We'll continue imaging the comet as long as the science team can
gain useful information, and then Stardust will get its well-deserved rest."
Stardust-NExT is a low-cost mission that is expanding the
investigation of comet Tempel 1 initiated by the Deep Impact
spacecraft. The mission is managed by JPL for NASA's Science Mission
Directorate in Washington. Lockheed Martin Space Systems in Denver
built the spacecraft and manages day-to-day mission operations.
The latest Stardust-Next/Tempel 1 images are online at:
http://www.nasa.gov/mission_
For more information about Stardust-NExT, visit:
http://stardustnext.jpl.nasa.
Source: NASA
