This photo from NASA shows the first comet dust embedded in a tiny wedge of aerogel. The grain entered from the lower right at supersonic speed and moved to the upper left, where it can be seen as a bright dot at the end of the carrot-shaped trail. The large oval cavity at lower right was blown out by shock waves created as the grain exceeded the sound barrier in the aerogel. (Click to enlarge)
The comet dust was extracted by University of California, Berkeley, researcher Christopher Snead using new nanomanipulation techniques developed at the campus's Space Sciences Laboratory. (Click to enlarge)
Comet Wild 2 Outgassing. The abundances and composition within comet grains will tell scientists about the conditions in the early solar system. Artist image courtesy of NASA (click to enlarge).
Stardust Comet Wild-2 Encounter. Artist image Image courtesy of NASA (click to enlarge).
Comet Particles Hitting Aerogel Grid. Artist image courtesy of NASA (click to enlarge).
Capsule Entry Into Earth's Atmosphere. After a seven-year journey, NASA's Stardust capsule returned to Earth in a great ball of fire. Check the video of the event. Stardust is not only the first mission to return samples from a comet, but it is the first sample return mission from the galaxy.
NASA's Stardust sample return capsule successfully landed at the U.S. Air Force Utah Test and Training Range at 2:10 a.m. Pacific time (3:10 a.m. Mountain time) January 16, 2006. Image courtesy of NASA (click to enlarge).
The Stardust sample return capsule was transported by helicopter from its landing site at the U.S. Air Force Utah Test and Training Range. This image shows the return capsule inside a protective covering. Image courtesy of NASA (click to enlarge).
When launched in 1999, Stardust flew without anyone having a clue as to how to get particles out of the aerogel after it came back. The Stardust JPL Aerogel is 99.8% air, 1,000 times less dense than glass and provides 39 times more insulating than the best fiberglass insulation. Image of Aerogel & Peter Tsou, JPL Scientist, courtesy of NASA (click to enlarge).
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First Stardust sample from Comet Wild 2 uncovered
Posted: Feb 01, 2006 06:05 pm EST
(Pythom.com) If the prophet can't come to the mountain, the mountain must come to the prophet. Yesterday the cool video of NASA's Stardust capsule return to Earth arrived. Today, we got the first pics with samples of dust from Comet Wild 2. Embedded in a tiny wedge of aerogel, the dust grain originating from stars millions of light years away entered the aerogel at a speed exceeding the sound barrier, the shock waves blowing out the oval cavity at lower right in the image.
In blind faith
When launched in 1999, Stardust flew without anyone having a clue as to how to get particles out of the aerogel after it came back. During Stardust's 7 year journey, a team at Berkeley have created tools for extracting both comet grains and interstellar dust grains.
A glass needle attached to a robotically-controlled micromanipulator is used to cut out the wedge-shaped piece of aerogel from a larger aerogel tile. The aerogel-embedded comet grain, still in the clean room at the Johnson Space Center in Houston, will be distributed to researchers for study. The trail is about 1 millimeter long, while the dust grain is only 10 microns across, or one-tenth the diameter of a human hair, reports University of California, Berkeley.
"Revelation of breathtaking results. Stay tuned!"
NASA reports that six particles have been removed from the aerogel. Most of these particles were 'potted' in epoxy and the epoxy was then sliced into very thin wafers. Infrared spectroscopy has been performed on the removed particles, and half of one of the removed aerogel cell has been examined with a X-Ray beam from a synchrotron.
"Some of the sliced wafers are being readied for a Transmission Electron Microscope to reveal the particle's mineralogy and petrology. As more of these processed samples reach the hands of eagerly awaiting analysts around the world, the pace of Wild 2 sample analyses - the central focus of this Preliminary Examination - will accelerate along with the revelation of breathtaking results. Stay tuned!" ends NASA the latest report.
The first sample from the galaxy
After a seven-year journey, NASA's Stardust capsule returned to Earth in a great ball of fire, with samples of dust from Comet Wild 2. Researchers onboard NASA's DC-8 aircraft spotted the meteor, "it was bright, slow, and glorious, and it pulled a wake lasting tens of seconds," they reported. Check out the video:
Stardust Video
The capsule successfully landed at the U.S. Air Force Utah Test and Training Range at 2:10 a.m. Pacific time (3:10 a.m. Mountain time) January 16, 2006, containing cometary and interstellar samples gathered by the Stardust spacecraft. Stardust is not only the first mission to return samples from a comet, but it is the first sample return mission from the galaxy.
Based on earlier work with glass cosmic-ray detectors on the Mir space station, Westphal of Berkeley University developed an automated microscope to digitally photograph the entire area of the aerogel in patches - the size of a salt grain - that can be viewed later in search of dust particles. The lengthy but exciting search for dust grains will be conducted by Internet volunteers.
Based on previous measurements of interstellar dust by both the Ulysses and Galileo spacecrafts, Westphal expects to find approximately 45 grains of submicroscopic dust in the collector, a mosaic of tiles of lightweight aerogel forming a disk about 16 inches in diameter - nearly a square foot in area - and half an inch thick.
Though those searching for pieces of Wild 2's tail will easily be able to pick out the thousands of cometary dust grains embedded in the front of the detector, finding the 45 or so grains of interstellar dust stuck in the back of the detector won't be so easy.
Thanks to a grant from NASA and assistance from the Planetary Society, however, Westphal and his colleagues at the Space Sciences Laboratory have created a "virtual microscope" that will allow anyone with an Internet connection to scan some of the 1.5 million pictures of the aerogel for tracks left by speeding dust. Each picture will cover an area smaller than a grain of salt.
If you joined the SETI@home search for intelligent life in the universe, you might also want to join this project, called Stardust@home.
University of California, Berkeley, researchers invite Internet users to help them in the search for the grains of interstellar dust captured by the aerogel at Stardust spacecraft. This aerogel (a novel, silicon-based sponge 100 times lighter than water) array, which was mounted atop the Stardust spacecraft, was used to collect the interstellar dust particles as well as dust from the tail of comet Wild 2, dating from the origins of the solar system some 4.5 billion years ago.
"Like SETI@home, which is the world's largest computer, we hope Stardust@home will also be a large computer, though more of a neural network, using brains together to find these grains," said Bryan Mendez of the Center for Science Education at the Space Sciences Laboratory.
"Twenty or 30 years ago, we would have hired a small army of microscopists who would be hunched over microscopes focusing up and down through the aerogel looking for the tracks of these dust grains," said Westphal. "Instead, we developed an automated microscope to scan the aerogel and hope to use volunteers we have trained and tested to search for these tracks."
The Web-based virtual microscope will be made available to the public in mid-March, even before all the scans have been completed in a cleanroom at Houston's Johnson Space Center. In all, Westphal expects to need some 30,000 person hours to look through the scanned images at least four times. Searching each picture should take just a few seconds, but the close attention required as the viewer repeatedly focuses up and down through image after image will probably limit the number a person can scan in one sitting.
To insure that the volunteer scanners know what they're doing, each must pass a test where he or she is asked to find the track in a few test samples. To judge the reliability of each volunteer - and to provide some reward in what for most will be a fruitless search - the team also plans to throw in some ringers with and without tracks.
"We will throw in some calibration images that allow us to measure the volunteers' efficiency," Westphal said.
If at least two of the four volunteers viewing each image report a track, that image will be fed to 100 more volunteers for verification. If at least 20 of these report a track, UC Berkeley undergraduates who are expert at spotting dust grain tracks will confirm the identification. Eventually, the grain will be extracted for analysis. Discoverers will get to name their dust grains.
Stardust@home website
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