Protein on comet hints at life in outer space
China Daily | Updated: 2009-08-19 07:57
LOS ANGELES: The amino acid glycine, a fundamental building block of proteins, has been found in a comet for the first time, bolstering the theory that raw ingredients of life arrived on Earth from outer space, scientists said on Monday.
Microscopic traces of glycine were discovered in a sample of particles retrieved from the tail of comet Wild 2 by the NASA spacecraft Stardust deep in the solar system some 390 million km from Earth, in January 2004.
Samples of gas and dust collected on a small dish lined with a super-fluffy material called aerogel were returned to Earth two years later in a canister that detached from the spacecraft and landed by parachute in the Utah desert.
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