PENNSYLVANIA, USA — While NASA's Artemis mission has yet to lift off, another mission has crash-landed — but that was the plan.
"This mission is demonstrating new types of technology for planetary defense as well as performing a really large science experiment," said Mallory DeCoster, a member of the impact team for NASA's Double Asteroid Redirection Test (DART).
The goal was to have an unmanned spacecraft smash into a binary asteroid system seven million miles away from Earth in an attempt to alter its orbit.
"It's far enough where the asteroid poses no threat to Earth. However, it's close enough that earth-based telescopes positioned all around the planet can observe the changes that will occur."
More specifically, the spacecraft targeted Dimorphos, a moonlet of the much larger Didymos.
"Once we nudge it a bit, all we have to do is watch it for a day, a week, a month, and we'll be able to get a good sense of how we did. If we were nudging an asteroid orbiting the sun, we could have to wait years to perform that measurement."
There are a couple of reasons why NASA scientists didn't create a much less costly experiment here on Earth.
"We get to perform one of the largest and fastest hypervelocity experiments ever done by man. This is something so big and so fast it could never be accomplished here in a lab on Earth," DeCoster said. "You rely on your models, but models are never reality. We really need experimental data to inform our models."
DeCoster said that slowing Dimorphos' orbit around Didymos by 73 seconds or more would make this experiment a success. It would also prove that this method of asteroid redirection would be a way to safely protect our planet from an earthbound asteroid in the future.
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