An asteroid measuring about a mile wide is on a deadly journey that could hurtle it into Earth in the year 2880 and end mankind forever. The good news is that scientists have already figured out how to stop it.
Previous studies observing the asteroid suggest that if it crashes into the Atlantic Ocean, it would be like a 60,000-megaton explosion. The aftermath would cause tsunami waves that measure 200 feet high. The result would be the complete extinction of most human and animal life on the planet.
Although the asteroid's odds of actually hitting Earth in 2880 is a one-in-300 chance, it's still the most likely candidate of any asteroid we've observed yet getting close enough to smash into the planet and causing large damage.
Fortunately, scientists already have a plan to protect the planet from certain doom, based on what they currently know about asteroids, which are not solid masses, but actually piles of cosmic rocks. Gravity pulls these rocks together and the friction of the asteroid's movement holds them in place.
Asteroid 1950 DA is spinning so quickly, that in theory, its rocks should be flying off of it. Its rotation is so fast, that it experiences what scientists call negative gravity. Basically, if someone could stand on the asteroid, they would immediately fly off into space.
"We knew from previous work that this asteroid was rotating faster than it should be, and we wanted to know why," says Ben Rozitis, a postdoctoral researcher at the University of Tennessee.
Centripetal forces, that thing that holds you in your seat when you ride through a roller coaster's loop, is holding those rocks together. Because the asteroid is so big, it spins faster than normal.
Understanding how these forces work is key in figuring out how to stop the asteroid from smashing into Earth.
"Following the February 2013 asteroid impact in Chelyabinsk, Russia, there is renewed interest in figuring out how to deal with the potential hazard of an asteroid impact," says Rozitis. "Understanding what holds these asteroids together can inform strategies to guard against future impacts."
Normally, scientists would try to hit the asteroid with something that makes it change course. However, with the size of Asteroid 1950 DA, there's a chance that this would only break up its rocks, creating smaller, albeit still dangerous, asteroids.
Instead, since we have the luxury of time, scientists recommend attempting maneuvers that make small changes to the asteroid over time, allowing it to break up at a slower rate.
