(Photo courtesy NASA/JHUAPL)
Johns Hopkins Applied Physics Lab’s latest space mission: Flying a satellite into an asteroid.
Scientists from the Laurel-based lab recently got the go-ahead from NASA to move forward on design of a spacecraft that could land on an asteroid, and deflect it from a collision course with Earth. The refrigerator-sized spacecraft would be the centerpiece of a mission called Double Asteroid Redirection Test, or DART.
The problem they’re trying to solve may recall certain late 1990s blockbusters. In this case, however, there isn’t imminent danger and the asteroids don’t need to be broken apart. As the JHU Hub explains, it just takes a little nudge:
DART would use what is known as a kinetic impactor technique—striking the asteroid to shift its orbit. The impact would change the speed of a threatening asteroid by a small fraction of its total velocity, but by doing so well before the predicted impact, this small nudge will add up over time to a big shift of the asteroid’s path away from Earth.
NASA tracks asteroids that approach “near-Earth” from the ground. The most recent large asteroid to catch astronomers’ attention came within a mere 1.1 million miles of Earth in April.
DART has one goal: planetary defense. While saving the planet would be an obvious need, the satellite could also target asteroids that are large enough to do “regional damage.” In a test that would take place in 2024, when the satellite would look to knock one of a twin asteroid called Didymos off its course. This is only a test, and the 530-ft. asteroid is not on a course for Earth. Here’s what it would look like:
“Since we don’t know that much about their internal structure or composition, we need to perform this experiment on a real asteroid,” JHUAPL’s Andy Cheng said in a statement. “With DART, we can show how to protect Earth from an asteroid strike with a kinetic impactor by knocking the hazardous object into a different flight path that would not threaten the planet.”