After NASA and the Johns Hopkins Applied Physics Laboratory deliberately crashed a space probe into an asteroid two weeks ago, astronomers anxiously monitored the distant space rock to see if the mission was a triumph or a failure to launch. This afternoon, NASA announced the suicide mission was a huge success, making great strides for the future of planetary defense missions.
The Double Asteroid Redirection Test (DART), which was launched late last year, was designed to test our ability to deflect an asteroid from hitting Earth. Such an impact could wipe out most life on Earth, just like the giant space rock that killed off the non-avian dinosaurs 65 million years ago. Fortunately, asteroids, even large ones, are not particularly difficult to deflect, particularly if you get to them early: a tiny change in velocity years in advance can turn an extinction-event-causing asteroid into one that misses Earth entirely.
