NASA, if your memory is good enough, sent a spacecraft to tangle with an asteroid late last year. The DART or Double Asteroid Redirection Test came to a conclusion last night when the 600kg satellite collided with its target out in space.
The plan was to lob the DART satellite at the Dimorphos asteroid and see if it makes any difference to its trajectory. Most of the DART was just weight with some basic navigation and propulsion systems, intended to collide with the Didymos satellite orbiting Dimorphos. Unfortunately, Didymos wasn’t playing ball so NASA sent it at the roughly 150-metre Dimorphos object.
A well-thrown DART
ATLAS observations of the DART spacecraft impact at Didymos! pic.twitter.com/26IKwB9VSo
— ATLAS Project (@fallingstarIfA) September 27, 2022
DART successfully impacted. The last few images it transmitted showed its target looming up, but a tweet shows the impact itself from a distance. It’s enough to make Michael Bay bite a chunk out of his clapperboard but better images are on the way.
An Italian CubeSat, LICIACube, has been following the DART spacecraft. It should transmit the effects of impact back for study. The Double Asteroid Redirection Test was about 3 metres on its longest side. It’s a little like firing a bullet at a building, but there should be some interesting science produced afterwards.
NASA head Bill Nelson said, “It’s been a successful completion of the first part of the world’s first planetary defense test. I believe it’s going to teach us how one day to protect our own planet from an incoming asteroid. We are showing that planetary defense is a global endeavor and it is very possible to save our planet.”
It’s a little concerning that NASA’s administrator feels there’s a need for the DART planetary defence system but at least we’re building one. After all, we know what very large space rocks can do. South Africa possesses the largest known impact crater on the planet. Anything large enough to make a hole at least 160km in diameter (and possibly 300km in size) should probably be redirected elsewhere.