A NASA spacecraft has returned asteroid samples that hold not only the pristine building blocks for life but also the salty remains of an ancient water world.

Samples returned from an asteroid contain a surprising abundance of the basic ingredients of life. They were discovered to be rich in carbon, nitrogen and ammonia, with over 30 kinds of amino acids and the five nucleobases found in RNA and DNA. 1 The asteroid, Bennu, was targeted by a Nasa mission that returned a capsule to Earth in September 2023.

In other words, Bennu's samples provide further evidence that life's building blocks formed early in the solar system and could have been transported to Mars, other planets, moons, or asteroids capable of supporting prebiotic chemistry. It was reported this week there's strong evidence of liquid water, not just frozen ice, on the Red Planet.