Extraterrestrial source confirmed for comet’s amino acids
A building block of proteins found in samples from an icy comet’s halo suggests that the ingredients of life could have hitched a ride to early Earth, researchers reported August 16 at a meeting of the American Chemical Society.
“The early Earth was bombarded with comets and meteorites,” says Jamie Elsila of NASA’s Goddard Space Flight Center in Greenbelt, Md., who led the new analysis. “This is one more clue to what ingredients could have been present on the early Earth and how they could have gotten there.”
NASA’s Stardust spacecraft collected the study samples when it flew through the gassy halo, or coma, of the comet Wild 2 (pronounced “Vilt-2”) in 2004. Two years later the collecting device parachuted to Earth, landing in the dark of night in Utah. Previous analyses by Elsila’s NASA colleagues Daniel Glavin and Jason Dworkin revealed that the samples contained amino acids, the building blocks of proteins.