Scientists find evidence that an asteroid contains tryptophan

An essential amino acid that is mistakenly believed to cause drowsiness after eating turkey has been found in an asteroid for the first time, giving scientists clues to the origin of life on Earth.

​ An essential amino acid that is mistakenly believed to cause drowsiness after eating turkey has been found in an asteroid for the first time, giving scientists clues to the origin of life on Earth. Read More Breaking News, Latest News and Videos | CNN