Most space missions don’t intend to crash their spacecraft. But that’s just what NASA has in mind for its upcoming Double Asteroid Redirection Test (DART) mission, when it will smash a spacecraft into an asteroid to see if that’s a viable way to protect Earth from potentially dangerous asteroid impacts. The agency is preparing for the launch of the mission later this month.
While the large majority of asteroids that we spot whip harmlessly past Earth, a small number are termed “Potentially Hazardous Objects” which could impact the planet. With developments in technology, we’re getting better at spotting these potential threats. But what do we do if we spot a chunk of rock headed for our planet? The DART project is a test of a planetary defense concept that involves crashing a craft into an asteroid.
Illustration of NASA’s DART spacecraft and the Italian Space Agency’s (ASI) LICIACube prior to impact at the Didymos binary system. NASA/Johns Hopkins, APL/Steve Gribben
DART will head toward a pair of asteroids: One larger body called Didymos, and one smaller one called Dimorphos. While neither of these asteroids is actually posing any danger to Earth, this will be a practice run for what could happen if an asteroid were threatening the planet. DART will impact into Dimorphos and attempt to adjust its trajectory, with the results being observed by Earth-based telescopes.
“The DART spacecraft, the main body of it is about 100 times smaller than Dimorphos, the asteroid that it’s targeting. So you can see this isn’t going to destroy the asteroid,” explained Nancy Chabot, DART coordination lead at Johns Hopkins University Applied Physics Laboratory (APL), in a briefing. “It’s just going to give it a small nudge. It’s actually going to deflect its path around the larger asteroid. So we’re demonstrating asteroid deflection in this double asteroid system.”
The DART spacecraft will guide itself using technology called SmartNav, which uses computational algorithms to locate the Dimorphos asteroid and point the craft toward it. “Never in my life would I have thought I would take a couple hundred million dollar spacecraft and crash it into an asteroid,” said Michelle Chen, leader of the SmartNav team at APL, with a laugh.
The launch of DART is scheduled for Tuesday, November 23 at 10:20 p.m. PT, using a SpaceX Falcon 9 rocket from Vandenberg Space Force Base in California. The spacecraft will head out into the solar system and should arrive at the binary asteroid system in fall 2022 to attempt its impact and deflection maneuver.