NASA’s DART mission will test a planetary defense strategy by smacking an asteroid

If all goes well, a spacecraft that NASA launched last November will smash itself to bits against an asteroid on Monday.

If all goes absolutely perfectly, that impact will jostle the asteroid into a slightly different orbit, meaning that for the first time, humans will have changed the trajectory of a celestial object.

Making history, however, is incidental. The real mission is to defend the planet.

No need to panic: The target space rock has no chance of striking Earth, nor does any other known asteroid for at least half a century. This NASA mission, operated by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., is testing a technique for redirecting an asteroid in case future Earth folk really need to bat one out of the way.

The basic idea could not be simpler: Hit it with a hammer! But the degree of difficulty is high, in part because no one has ever actually seen the asteroid NASA plans to nudge. It is a moonlet named Dimorphos that is about the size of a football stadium.

Sky watchers operating the world’s highest-powered telescopes detect the moonlet only as a shadow that crosses the larger asteroid it orbits, Didymos, as the two circle the sun together. The pair make up a “double asteroid,” a common arrangement in our solar system.

Here’s how the $330 million Double Asteroid Redirection Test (DART) is designed to work:

Leave a Comment

Your email address will not be published.