Unfortunately for doomsdayers, the world isn’t going to end tomorrow when an asteroid comes close to the Earth. But it is going to be one hell of a close shave, coming within 17,000 miles of the planet’s surface.
The asteroid in question, called 2012 DA14, was discovered by a small team of astronomers at the La Sagra Observatory in southern Spain on February 22, 2012. They found it using a specialized camera on one of the observatory's telescopes that’s designed to detect really fast moving objects. And because it's coming near Earth, the asteroid has been a huge source of interest for researchers.
2012 DA14 isn’t huge, about half the size of a football field and a little more than 147 feet in diameter. Astronomers figured out its trajectory, and concluded that there’s no chance the asteroid will end up hitting the Earth. But the predicted 17,000-mile pass is close—closer than some geosynchronous satellites, which typically orbit about 22,245 miles above the equator and support such important things as our communications network. (Thankfully, astronomers have ruled out the possibility of the asteroid taking out a satellite; these satellites actually have a higher likelihood of hitting each other than being hit by an asteroid.)