Say hello to 2013 YP139 — a newly discovered 0.4 mile (650 meter) wide asteroid spotted by NASA's recently re-started NEOWISE spacecraft. Preliminary calculations show it'll come within 300,000 miles from Earth — thus qualifying it as a potential headache.


Above: The six red dots in this composite picture indicate the location of the first new near-Earth asteroid seen by NASA's Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) since the spacecraft came out of hibernation in December 2013. Credit: NASA/JPL-Caltech

The asteroid is currently 27 million miles (43 million km) from Earth. It's extremely dark, like a piece of coal. 2013 YP139 is currently circling the sun in an elliptical orbit tilted to the plane of our solar system. It could swing by at a distance closer than the Earth is to the Moon, but it won't do so within the next century.


NASA is classifying it as a potentially hazardous object because of the uncomfortably close projected flyby distance, and because objects greater than a half mile in diameter could have worldwide effects.

Because it was just discovered, and because the calculations are still incomplete, it has yet to appear on NASA's NEO risk chart. NASA says that

NEOWISE will continue to detect asteroids and comets. The observations will be automatically sent to the clearinghouse for solar system bodies, the Minor Planet Center in Cambridge, Mass., for comparison against the known catalog of solar system objects and to determine orbit if the object is not known. A community of professional and amateur astronomers will provide follow-up observations, establishing firm orbits for the previously unseen objects.

The only real threat facing Earth right now is 2007 VK184:


This 425 foot (0.13 km) wide object has a 1 in 1,750 chance of hitting us, or a 99.94300000% chance of missing the Earth. This object has four chances of hitting us between 2048 to 2057.

[ NASA JPL ]