LOS ANGELES — A coal-colored asteroid as big as an aircraft carrier zipped by Earth on Tuesday in the closest encounter by such a massive space rock in more than three decades.
Scientists ruled out any chance of a collision but turned their telescopes skyward to learn more about the object known as 2005 YU55, which was discovered six years ago.
Its closest approach to Earth was pegged at 202,000 miles at 4:28 p.m. MST. That’s just inside the moon’s orbit; the average distance between Earth and the moon is 239,000 miles.
The last time a large cosmic interloper came that close to Earth was in 1976, and experts say it won’t happen again until 2028.
Scientists at NASA’s Deep Space Network in the California desert tracked the quarter-mile- wide asteroid since last week as it approached at 29,000 mph. Astronomers and amateur skygazers around the world kept watch too.
The Clay Center Observatory in Brookline, Mass., planned an all-night viewing party so children and parents could peer through research- grade telescopes and listen to lectures. The asteroid couldn’t be detected with the naked eye.
For those without a telescope, the observatory streamed video of the flyby live on Ustream, attracting several thousand viewers.
Asteroids are leftovers from the formation of the solar system 4.5 billion years ago.
“It’s a fantastic opportunity to educate the public that there are things out in space that we need to be aware of,” including this latest flyby, said observatory director Ron Dantowitz.
He added: “It will miss the Earth. We try to mention that in every breath.”
