Hayabusa’s Unsteady Touchdown

Transcripción

Hayabusa was Japan’s spacecraft sent to return samples from the asteroid Itokawa. Its touchdown became a test of a spacecraft already struggling to control its attitude, or orientation: two of its three reaction wheels had failed. On November nineteenth, 2005, Hayabusa made a soft landing in Itokawa’s MUSES Sea. It bounced back up, then settled into a stable position about half an hour later. But it was not properly aligned, and it lifted off again later that evening. The landing was documented. It is not, by itself, proof that the planned sample collection worked. On a later landing attempt, Hayabusa was supposed to fire small projectiles to kick up material for collection. Later data suggested the projectiles probably were not fired, though the chronicle says some material was clearly collected. It does not identify the returned grains or establish that they came from that planned sampling event. The capsule returned to Earth in June 2010. Hayabusa’s record is a reminder to distinguish a landing from a confirmed sample.