NASA's OSIRIS-REx Mission Uncovers Life's Building Blocks on Asteroid Bennu

When NASA scientists opened the sample return canister from the OSIRIS-REx asteroid sample mission in late 2023, they found something astonishing. Dust and rock collected from the asteroid Bennucontained many of life's building blocks, including all five nucleobases used in DNA and RNA, 14 of the 20 amino acids found in proteins, and a rich collection of otherorganic molecules. These are built primarily from carbon and hydrogen, and they often form the backbone of life's chemistry. For decades, scientists have predicted that early asteroids may have delivered the ingredients of life to Earth, and these findings seemed like promising evidence. Even more surprising, theseamino acidsfrom Bennu were split almost evenly between "left-handed" and "right-handed" forms. Amino acids come in two mirror-image configurations, just like our left and right hands, calledchiral forms.