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.

All forms of Earth life have specific chemicals in their makeup, such as amino acids and sugars. Scientists have known that asteroids hold molecules believed to be the precursors to these chemicals. By studying the Bennu samples, they hope to gain more insight into how these ingredients could have evolved.

Scientists have finally had a close look at the rubble collected by a spacecraft from the asteroid Bennu. Here's what they found inside and what it could tell us about the origin of life on Earth.