By studying samples from Kamo‘oalewa, researchers hope to determine whether it was once part of the Moon — and was chipped away during a collision event — or has escaped from the asteroid belt that circles between Mars and Jupiter. “This is still debatable,” says Marco Fenucci, a mathematician who studies the dynamics of small astronomical bodies at the European Space Agency, near Rome. No asteroids in the Solar System are known to come from the Moon.

The samples will also help researchers to understand how asteroids form and evolve, says Li.