An asteroid the size of an aircraft carrier has flown by Earth in the closest encounter by a massive space rock in more than 30 years.

The asteroid, named 2005 YU55, came within about 325,000 kilometers of the planet Tuesday evening . The U.S. space agency, NASA, said there was no chance that the spherical rock would collide with Earth or the moon. The asteroid was traveling at more than 46,670 kilometers per hour. It passed closer to Earth than the moon.

The last time an object the size of the asteroid traveled so near to Earth was in 1976. Scientists say it will be 2028 before another space object this large will fly by the planet.

A scientist at the University of Arizona discovered the YU55 asteroid in 2005.

NASA scientists planned to bounce radio waves off the asteroid and analyze the radar echoes. Those images should reveal details about the rock's surface features.

YU55 is about 400 meters in diameter. Scientists believe it has been passing by Earth for thousands of years. It is one of about 8,500 near-Earth objects that NASA has catalogued.