An asteroid named 2007 TU24, discovered on October 11, 2007 will approach Earth to as close as 334,000 miles. It’s diameter is between 50 and 200 feet (150 – 600 meters) and its closest approach is expected to be Jan 29 – Jan 30. There is no chance it will collide with Earth as it will be 50% further from Earth than the moon.

An object this size comes this close to Earth about once every five years, with impacts expected once every 37,000 years. The next time a near earth object of this size gets this close will be in 2027.

More details can be found and NASA’s Jet Propulsion Lab’s Near Earth Object website here. The site also provides java enabled displays of the projected path of the asteroid.