Every culture in history has thought they knew what the gods would be like

It’s been a busy month in space. The Japanese Hayabusa2 mission is orbiting Ryugu, a tiny near-Earth asteroid. A Chinese probe is about to place a lander on the far side of the Moon. Nasa’s InSight mission has arrived on Mars to measure “marsquakes” and the heat flowing from its interior. Virgin Galactic is testing a ship that can take tourists above the stratosphere.

Of all these, my attention is on OSIRIS-REx. (The name is a typical Nasa acronym; don’t ask.) This probe has also just arrived at a near-Earth asteroid, named Bennu, with essentially the same mission as Hayabusa2. It was the dream of the late Mike Drake, my first PhD advisor at the University of Arizona; after his death, the science team lead fell to Dante Lauretta, whose PhD director was my classmate, Bruce Fegley. And the rest of the science team are also friends of mine.

The holy grail of asteroid science for a long time has been to find asteroids with the same composition as those rare but important meteorites rich in water and carbon. Though science fiction stories talk about mining rare minerals from the asteroids, in fact water and rocket fuel would be what’s most in demand in the near future.