Scientist Daniel Glavin (Courtesy of Chris Gunn Winter,…)
Description: A meteorite that rained fragments on a frozen lake in Canada in January 2000 is revealing new insights on protein molecules thought to help explain the origins of life. The proteins can have two types of orientations — right- or left-handed, they are called — and life is not thought to be able to function without a mix of both. Scientists explored the presence of left-handed amino acids inside the meteorite fragments.
Researchers: Daniel Glavin of the NASA Goddard Space Flight Center in Greenbelt was the lead author of the research, published last month, along with Jason Dworkin, Aaron Burton and Jamie Elsila of the Goddard center and Christopher Herd of the University of Alberta in Canada.
Stage of research: The scientists have analyzed ground-up samples of the meteorites and found higher levels of left-handed versions of one type of amino acid than right-handed versions. Other types of amino acids in the meteorite didn't show the same disparity. The scientists were able to determine that the amino acids were created in space, by a non-biological process.
Implications: The finding raises questions about how the high levels of left-handed amino acids were created, and how the left-handed versions that are so vital in biology came to Earth in the first place. An excess of left-handed proteins was previously thought to have come only from biological processes. The finding makes it more difficult to predict life on other planets, such as Mars, because a high level of left-handed amino acids can no longer serve as proof of life.