Bet the dinosaurs wish they'd thought of this. NASA on Monday will attempt a feat humanity has never before accomplished: deliberately smacking a spacecraft into an asteroid to slightly deflect its orbit, in a key test of our ability to stop cosmic objects from devastating life on Earth. The Double Asteroid Redirection Test (DART) spaceship launched from California last November and is fast approaching its target, which it will strike at roughly 14,000 miles per hour (23,000 kph). To be sure, neither the asteroid moonlet Dimorphos, nor the big brother it orbits, called Didymos, pose any threat as the pair loop the Sun, passing some seven million miles from Earth at nearest approach. But the experiment is one NASA has deemed important to carry out before an actual need is discovered. "This is an exciting time, not only for the agency, but in space history and in the history of humankind quite frankly," Lindley Johnson, a planetary defense officer for NASA told reporters in a briefing Thursday. If all goes to plan, impact between the car-sized spacecraft, and the 530-foot (160 meters, or two Statues of Liberty) asteroid should take place at 7:14pm Eastern Time (2314 GMT), and can be followed on a NASA livestream. By striking Dimorphos head on, NASA hopes to push it into a smaller orbit, shaving ten minutes off the time it takes to encircle Didymos, which is currently 11 hours and 55 minutes - a change that will be detected by ground telescopes in the days that follow. The proof-of-concept experiment will make a reality what has before only been attempted in science fiction - notably films such as "Armageddon" and "Don't Look Up." Technically challenging As the craft propels itself through space, flying autonomously for the mission's final phase like a self-guided missile, its main camera system, called DRACO, will start to beam down the very first pictures of Dimorphos. "It's going to start off as a... |