As DART’s full name implies, this impact was no accident. It’s meant to shift the space rock’s trajectory by a tiny but noticeable amount—a change that observers will carefully confirm and track from afar with a plethora of ground- and space-based telescopes. In the future, if a dangerous asteroid is found on a collision course with Earth, we might use this same technique to nudge it off course and avert disaster. “We’re not blowing up the Death Star,” says Andy Rivkin, DART investigation team lead at the Johns Hopkins University Applied Physics Laboratory (APL), which runs the mission. “We’re using the momentum from the spacecraft to change the orbit of the asteroid.”
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