Big asteroid close encounter with Earth

(Reuters) - Black asteroid as big as an aircraft carrier zoomed past Earth on Tuesday, delighting astronomers who trained telescopes on the ancient body, hoping to learn more about its composition and origin.

With a diameter estimated at 400 meters, or about a quarter of a mile, asteroid 2005 YU 55 is the largest asteroid to pass close to Earth since 1976.



During closest approach, which took place at 18:28 EST, was in orbit of the moon, about 200,000 miles above the planet. It poses no threat either.

Thousands of professional and amateur astronomers have been tracking the asteroid with telescopes who want to learn more about what it is, how fast it spins, and in the end, where it came from.

"It was pretty easy to find," astronomer Ronald Dantowitz, director of student Clay Center Observatory in Brookline, Massachusetts, told Reuters. "It moves differently than the stars are moving. It looks like a giant rock floating through space."

With automated controls for tracking the asteroid seemed fixed in position, while the background stars are blurring, Dantowitz said. The asteroid, however, moving at about 30,000 miles per hour.

Astronomers believe YU 55 is visiting Earth for thousands of years, pushed from the main asteroid belt between Mars and Jupiter, the gravity of Jupiter elbowing.

The computer model simulates the asteroids path for the next 100 years shows that there is no chance they will hit the earth or the moon during that time, said Don Yeomans at NASA's Jet Propulsion Laboratory in Pasadena, California.

Astronomers do not expect to be a threat outside of the time either, but did not run models over 100 years.

Asteroids are of interest to scientists trying to connect to the solar system formed.

"It costs millions of dollars to send a spacecraft to a close encounter with an asteroid," said Dantowitz. "Instead, this comes to us. It is literally flowing through our yard."

YU 55 is believed to be one of the more common species, carbon-rich asteroids, although large. Its ancient rocks may contain water, metal and other materials that might be useful for space explorers.

NASA's next human space venture outside the International Space Station, $ 100 billion orbital research outpost flying about 240 miles above Earth, the asteroid mission, the goal for the 2025th