In 2010, a Japanese mission called Hayabusa returned to Earth from a seven-year space journey. It brought back not only images and data from its adventure, but also actual samples, small grains of rock from its target, the asteroid Itokawa. Just a handful of space missions have ever returned to Earth at all, let alone brought back pieces of their destinations. So Hayabusa’s samples are highly prized, and have been studied by many teams across the world.

Now, researchers from Arizona State