2005 YU55

2011 Flyby, whew.. that was close...

(AP) LOS ANGELES - An asteroid the size of an aircraft carrier is set to make a close but harmless swing by Earth on Tuesday. Scientists at NASA's Near-Earth Object Program, which tracks asteroids and comets, ruled out any chance of impact. They're using the close encounter to learn more about the space rock known as 2005 YU55.
NASA's Near-Earth Object Program

The last time a cosmic interloper this size came this close to Earth was in 1976 and it won't happen again until 2028. Since late last week, antennas at the space agency's Deep Space Network in California have been monitoring the quarter-mile-wide asteroid as it approaches from the direction of the sun.

The Arecibo Observatory in Puerto Rico planned a viewing Tuesday when the asteroid is set to make its closest pass at a distance of 202,000 miles at 6:28 p.m. EST.

Researchers will analyze radar images to glean details about the asteroid's surface features and shape.