https://www.vice.com/en_us/article/akendp/watch-nasa-dart-test-live > A spacecraft will deliberately crash into an asteroid at 14,000 miles per hour on Monday in what will be the very first test of a planetary defense strategy to alter the trajectories of dangerous space rocks that could one day collide with Earth. > Launched in 2021, NASA’s Double Asteroid Redirection Test (DART) is now closing in on a half-mile-wide asteroid called Didymos, which is orbited by an even smaller asteroid called Dimorphos, or “Didymoon.”