Later this year two spacecraft will arrive at separate asteroids to map them, grab some samples and head home. It’s not really a race of course, their respective itineraries have been planned long in advance. If all goes well, and there’s no reason why it shouldn’t, JAXA’s Hayabusa 2 will arrive at asteroid Ryugu in June of this year, with NASA’s OSIRIS-REx reaching asteroid Bennu in August. Both will then embark on complex remote sensing studies of their respective targets, before collecting samples that will be brought back to Earth for detailed laboratory characterisation. Which one will get home first? Well, Hayabusa 2 should be back long before OSIRIS-REx, dropping a capsule containing its precious samples in the Australian desert in late 2020. OSIRIS-REx doesn’t make it back until 2023. That’s the plan anyway! Of course things don’t always go exactly as scheduled. The earlier Hayabusa 1 spacecraft took a much more roundabout route back to the mother planet than the mission planners had initially envisaged, but that’s another story.

OSIRIS-REx Spacecraft at Asteroid Bennu (image: NASA)

Hayabusa 2 spacecraft at Asteroid Ryugu (image: JAXA)

Photo of 5000 metres European Final, Zurich 2014 – Maximilian Dersch/Wikipedia