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Making Heads or Tails of Comet Dust

(Image - Stardust Probe - courtesy of NASA) Last week, a team of SSRL researchers began analyzing particles taken from the tail of a comet.

The particles came from the Stardust NASA mission, which clipped the tail of comet Wild 2 (pronounced Vilt). Comet particles skidded through ultra-light aerogel and remained stuck there for the journey back to earth. 

SLAC is one of many laboratories identifying elements in the samples, which arrived from NASA in thin aerogel slices.

“We are very excited to be mapping out the elemental abundance of the comet particles,” said SLAC's Sean Brennan.

The purpose of the mission was to catch ancient unspoiled material from the tail of the Wild 2 comet that might tell about the birth of the solar system. As it is, scientists know very little about what makes up interplanetary material.

Minerals on earth have cycled through so many natural processes that they look vastly different than they did at the beginning of the solar system. Wild 2 offers a special opportunity to sample a relatively unaltered comet because it existed on the edges of our solar system for billions of years before approaching the sun for the first time just 35 years ago.

Using x-rays from the SPEAR3 storage ring, Brennan hopes to look at five separate particle impacts by the end of the run. He is also planning for another run before the end of the year.

Because the analysis is a collaborative effort, the team will share data with participating scientists around the world. For this SPEAR3 run, scientists from U.C. Berkeley’s Space Science Laboratory and the Stanford Chemistry Department will be on hand to lend their expertise.


—Erik Vance
   SLAC Today, March 9, 2006