This pair of images shows the before-and-after comparison of the part of comet Tempel 1 that was hit by the impactor from NASA's Deep Impact spacecraft. Image credit: NASA/JPL-Caltech/University of Maryland/Cornell › Full image and caption
This pair of images shows the area affected by the impactor released by NASA's Deep Impact spacecraft in July 2005. On the left, the image from Deep Impact shows a dark mound about 50 meters (160 feet) in size. It is inside a yellow circle that shows the area hit by the impactor released by Deep Impact. Image credit: NASA/JPL-Caltech/University of Maryland/Cornell › Full image and caption
This image layout depicts changes in the surface of comet Tempel 1, observed first by NASA's Deep Impact Mission in 2005 (top right) and again by NASA's Stardust-NExT mission on Feb. 14, 2011 (bottom right). Image credit: NASA/JPL-Caltech/University of Maryland/Cornell › Full image and caption
This image layout depicts changes in the surface of comet Tempel 1, observed first by NASA's Deep Impact Mission in 2005 (top right) and again by NASA's Stardust-NExT mission on Feb. 14, 2011 (bottom right). Image credit: NASA/JPL-Caltech/University of Maryland/Cornell › Full image and caption
This pair of images shows a before-and-after comparison of the area on comet Tempel 1 targeted by an impactor from NASA's Deep Impact spacecraft in July 2005. Image credit: NASA/JPL-Caltech/University of Maryland › Full image and caption
This image shows the area where scientists predicted an impactor released from NASA's Deep Impact spacecraft in July 2005 would hit the surface of comet Tempel 1. › Full image and caption
This image mosaic shows four different views of comet Tempel 1 as seen by NASA's Stardust spacecraft as it flew by on Feb. 14, 2011. The images progress in time beginning at upper left, moving to upper right, then proceeding from lower left to lower right. Image credit: NASA/JPL-Caltech/Cornell › Full image and caption
NASA's Stardust-NExT mission took this image of comet Tempel 1 at 8:39 p.m. PST (11:39 p.m. EST) on Feb 14, 2011. The comet was first visited by NASA's Deep Impact mission in 2005. Image credit: NASA/JPL-Caltech/Cornell › Full image and caption
This image obtained by NASA's Stardust spacecraft shows a side of the nucleus of comet Tempel 1 that has never been seen before. In the image, three terraces of different elevations are visible, with dark, banded scarps, or slopes, separating them. Credit: NASA/JPL-Caltech/Cornell › Full image and caption
These two images show the different views of comet Tempel 1 seen by NASA's Deep Impact spacecraft (left) and NASA's Stardust spacecraft (right). › Full image and caption
This series of images shows the area where NASA's Deep Impact probe collided with the surface of comet Tempel 1 in 2005. The view zooms in as the images progress from top left to right, and then bottom left to right. Image credit: NASA/JPL-Caltech/Univ. of Maryland Larger image
Comet Tempel 1 Six Years Later
This image shows the surface of comet Tempel 1 as seen before and after NASA's Deep Impact mission sent a probe into the comet in 2005. Image credit: NASA/JPL-Caltech/Cornell/Univ. of Maryland › Larger image
Deep Impact Site in 3-D
This 3-D image, or anaglyph, shows the region where NASA's Deep Impact mission sent a probe into the surface of comet Tempel 1 in 2005. Image credit: NASA/JPL-Caltech/Cornell › Larger image
This pair of images shows the before-and-after comparison of the part of comet Tempel 1 that was hit by the impactor from NASA's Deep Impact spacecraft. Image credit: NASA/JPL-Caltech/University of Maryland/Cornel › Larger image
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 (11:40 p.m. EST) at a distance of approximately 178 kilometers (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.
