Discussion

NASA’s DART spacecraft changed an asteroid’s orbit around the sun

p0w3n3d: Wow, that's the first step!However, the most efficient method would be actually land (I know - maybe even impossible?) on it, and use propellers to change its trajectory. We don't have too much throwaway high-tech to crash it on asteroids...

prism56: Interesting. I'd not considered the loss of mass as a means of propulsion.Obviously there was the kinetic energy transfer but the impact ejacted some of the asteroids mass opposite to it's trajectory further increasing it's trajectory change.Cool demonstration, hopefully not needed one day.

messe: That's how rockets work.

prism56: Yeah, I sort of meant in the context of an object losing its mass, it's seldom used on earth as the effects are small but on the timescale/distance/speeds of an asteroid it could have noticeable effects.Rockets are using mass loss but there's more going on with the rapidly expanding gas causing the increased impulse.

Incipient: I'm not sure this is actually a necessary explanation...but while propellers technically COULD function in space (not a perfect vacuum, right?)...they're basically going to be useless.

wartywhoa23: Well done, DART, which country did you aim it to?

yubainu: That's interesting news. I wonder how much kinetic energy it had. This accumulation of information might be useful if an asteroid were to hit the Earth someday. At the very least, it's more realistic than sending oil drilling experts to an asteroid.

XYen0n: Impact is actually a more efficient method, as it avoids the fuel consumption required for deceleration and soft landings.