The Double Asteroid Redirection Test (DART): Hitting an Asteroid Head On

Earth moves through a dangerous neighborhood. Astronomers estimate there are about 1,000 near-Earth asteroids larger than 1 kilometer—big enough to cause a global disaster. About 90 percent of them have been identified. Far less is known about smaller asteroids. All told, about 100 tons of extraterrestrial matter falls onto Earth every day, mostly in the form of harmless dust and an occasional meteorite. NASA’s Double Asteroid Redirection Test (DART) will be the first ever space mission to demonstrate ast