Comet 81P
Quick Summary
Comet 81P/Wild 2 is a comet that was visited by NASA's Stardust spacecraft in 2004. Comets are celestial bodies composed primarily of volatile ices like water, carbon dioxide, and ammonia, mixed with dust. When a comet approaches the Sun, these ices sublimate, creating a visible coma and often a tail that can extend millions of kilometers.12
The Stardust mission collected dust samples from Comet 81P/Wild 2, which revealed the presence of high-temperature materials that must have formed closer to the Sun. This suggests that material in the early solar system was mixed during planet formation. The nucleus of Comet 81P/Wild 2 was observed to have a surface covered in large, flat-floored depressions, possibly indicating a very "new" cometary surface that had not previously been close to the Sun.1
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cometSpacecraft exploration of comets…dust from the coma of Comet 81P/Wild 2. At a flyby speed of 6.1 km per second (13,600 miles per hour), the dust samples would be completely destroyed by impact with a hard collector. Therefore, Stardust used a material made of silica (sand) called aerogel that had a very low…
Read More…dust from the coma of Comet 81P/Wild 2. At a flyby speed of 6.1 km per second (13,600 miles per hour), the dust samples would be completely destroyed by impact with a hard collector. Therefore, Stardust used a material made of silica (sand) called aerogel that had a very low…
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micrometeoroid…launched in 1999, flew past Comet Wild 2 in early 2004, collecting particles from its coma for return to Earth. In 2003 Japan’s space agency launched its Hayabusa spacecraft, which also returned small amounts of surface material, comprising fragments and dust, from the near-Earth asteroid Itokawa for laboratory analysis.
Read More…launched in 1999, flew past Comet Wild 2 in early 2004, collecting particles from its coma for return to Earth. In 2003 Japan’s space agency launched its Hayabusa spacecraft, which also returned small amounts of surface material, comprising fragments and dust, from the near-Earth asteroid Itokawa for laboratory analysis.
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