A near-Earth object will be speeding past the Earth at about 80,000 miles from the planet. That's about one-third the distance to the Moon. It's uncertain whether it's a man-made object or a small asteroid. What makes this sighting especially interesting is that asteroids as small as 10 meters (about 33 feet) can be detected two days in advance.
2010 AL30: Asteroid or Space Junk? (Updated) : Discovery News