Amino Acid Found in Stardust Comet Sample

August 17th, 2009
Amino Acid Found in Stardust Comet Sample

Written by Nancy Atkinson

Artists concept of the stardust spacecraft flying throug the gas and dust from comet Wild 2. Credit: NASA/JPL

NASA scientists studying the comet samples returned by the Stardust spacecraft have discovered glycine, a fundamental building block of life. Stardust captured the samples from comet Wild 2 in 2004 and returned them to Earth in 2006. "Glycine is an amino acid used by living organisms to make proteins, and this is the first time an amino acid has been found in a comet," said Dr. Jamie Elsila of NASA's Goddard Space Flight Center. "Our discovery supports the theory that some of life's ingredients formed in space and were delivered to Earth long ago by meteorite and comet impacts."

Proteins are a major component of all living cells, and amino acids are the building blocks of protein. Just as the 26 letters of the alphabet are arranged in limitless combinations to make words, life uses 20 different amino acids in a huge variety of arrangements to build millions of different proteins./.../