Last updated on April 18, 2014 at 17:24 EDT
Gem of a Comet Particle
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Gem of a Comet Particle

March 3, 2006
This image shows a comet particle collected by the Stardust spacecraft. The particle is made up of the silicate mineral forsterite, which can found on Earth in gemstones called peridot. It is surrounded by a thin rim of melted aerogel, the substance used to collect the comet dust samples. The particle is about 2 micrometers across.