Asteroid to Hit Earth? NASA Builds Craft to Find Out

With a big asteroid possibly heading for Earth in 2182, what are scientists to do? Build an unmanned spacecraft to give that hunk of rock a closer look, the Arizona Republic reports. NASA and the University of Arizona are is designing the $1 billion project, called OSIRIS-REx, which is set to launch in 2016. If all goes well, it will reach asteroid Bennu two years later, analyze its composition, and scrape off a sample—all to help scientists determine how likely the quarter-mile-wide asteroid is to strike Earth.

One calculation puts the odds of a Bennu strike at 1 in 1,800, so don't lose any sleep—but it would hit with the force of 100 nuclear warheads and carve out a 4-mile-wide crater. So experts at Lockheed Martin had good reason to approach University of Arizona professors about the project a few years back. As it stands, Bennu comes within about 280,000 miles of Earth every six years and is considered dangerous because of its proximity and size. (More asteroid stories.)