Astronomy Picture of the Day (original) (raw)

Discover the cosmos!Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2025 February 12

Asteroid Bennu Holds the Building Blocks of Life
Video Credit: Data: NASA, SVS, U. Arizona, CSA, York U., MDA; Visualizer: Kel Elkins (lead, SVS); Text: Ogetay Kayali (Michigan Tech U.)

Explanation: What can a space rock tell us about life on Earth? NASA's OSIRIS-REx spacecraft made a careful approachto the near-Earth asteroid 101955 Bennu in October of 2020 to collect surface samples. In September 2023, the robotic spaceship returned these samples to Earth. A recent analysis has shown, surprisingly, that the samples contained 14 out of the 20 known amino acids that are the essential building blocks of life. The presence of the amino acids re-introduces a big question: Could life have originated in space? However, the protein building blocks themselves held another surprise -- they contained an even mixture of left-handed and right-handed amino acids -- in contrast to our Earth which only has left-handed ones. This raises another big question: Why does life on Earth have only left-handed amino acids? Research on this is sure to continue.

Tomorrow's picture: interstellar dust clouds

Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)
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