Dozens of robotic spacecraft have studied the worlds of the solar system from up close. They’ve told us a lot about those worlds, and about the birth and evolution of the entire solar system. But to really get down to the nitty-gritty, you need the nitty-gritty — samples of dust and rock to study in the lab.

So far, space missions have collected samples of four worlds other than Earth: the Moon, two asteroids, and a comet. Astronauts and robots have collected almost half a ton of samples from the Moon. The samples of the others are tiny.

Still, those bits are treasures. In the lab, scientists can study the samples with the most advanced equipment yet devised — stuff that could never be flown in space. Different groups can study the samples, applying different techniques to help confirm the results. And some of the samples can be stored for future scientists, who will have equipment and techniques that haven’t yet even been dreamed of.

The most recent samples were captured by a Japanese mission to the asteroid Ryugu. It delivered five grams of material to Earth in 2020. From those tiny bits of rock and dust, scientists have learned that Ryugu dates back to the birth of the solar system. They’ve also found that some minerals on the surface formed in a wet environment, and much more.

Scientists are scheduled to get samples of another asteroid this weekend, when a NASA mission parachutes to Earth.
 

Script by Damond Benningfield