Stardust captured particles from the comet's tail in a tennis-racket sized collection unit made with blocks of aerogel, a strong, lightweight silica glass that is 99.8 percent air and looks like frozen smoke.Stardust will launch its capsule containing the comet particles once it nears Earth's atmosphere. The capsule will then enter our atmosphere and will land in Utah with the help of a parachute. Those who are living in California, Nevada and Utah can see the Stardust capsule burn through the atmosphere. From Desert News:
"The fundamental reason for this mission is that we are collecting what we believe are the best preserved samples of the formation of our solar system and they are preserved because they formed these comet bodies beyond the major planets out beyond Neptune," said principal investigator Don Brownlee of the University of Washington.
It will come in at 29,000 miles per hour, its heat shield creating a long blaze in the dark heavens. For those in the best places, "Stardust's return home will look like a bright, fiery meteor streaking from northwest to southeast," said Patrick Wiggins, NASA solar system ambassador to Utah and Nevada.NASA is also covering the landing on its NASA TV. You can view it online here.
While it should be visible across a large swath of the northwestern United States, its landing state may not be a good place to see it. Wiggins said the best places to see it may be along a line from Elko, Nev., to Wendover. People there may also hear its sonic boom.