Scientists detected all five nucleobases -- building blocks of DNA and RNA -- in samples returned from asteroid Bennu by NASA's OSIRIS-REx mission.

Pristine samples of the asteroid Bennu transported to Earth contain the "basic building blocks" for life, shedding new light on the perennial question of how life began on our planet. The revelation, in two studies published Wednesday, is the result of work on just 120 grams of material -- about…