Japanese scientists detected all five nucleobases — building blocks of DNA and RNA — in samples returned from asteroid Bennu by NASA’s OSIRIS-REx mission. NASA’s OSIRIS-REx mission brought back 121.6 grams of asteroid Bennu,

Asteroids, small airless bodies within the inner solar system, are theorized to have contributed water and chemical building blocks of life to Earth billions of years ago. Although meteorites on Earth come from asteroids,

Rock and dust samples brought back from the near-Earth asteroid Bennu contain organic matter, including amino acids and all five DNA and RNA bases, as well as salts that formed early in the history of Bennu's parent body.