Rahul Rao in Nature:
Humans have for the first time proved that they can change the path of a massive rock hurtling through space. NASA has announced that the spacecraft it slammed into an asteroid on 26 September succeeded in altering the space rock’s orbit around another asteroid — with better-than-expected results.
Agency officials had estimated that the Double Asteroid Redirection Test (DART) spacecraft would ‘nudge’ the asteroid Dimorphos closer to its partner, Didymos, and cut the time it takes to orbit around that rock by 10–15 minutes. At a press conference on 11 October, researchers confirmed that DART in fact cut the orbital time by around 32 minutes.
Neither asteroid was a threat to Earth, but the agency tested the manoeuvre to prove that humanity could, in principle, deflect a worrisome space rock heading for the planet.