Intelligencer Journal/Lancaster New Era

Asteroid will make close call next week
BY BRIAN VASTAG, The Washington Post

A close encounter of the rocky kind is set for Friday when an office building-size asteroid will speed past the Earth faster than a bullet and closer than some communications and GPS satellites.

It will be the nearest recorded brush with a space rock so large, NASA scientists said Thursday.

The good news: There's no chance of an impact. At its closest, asteroid 2012 DA14 will pass 17,000 miles above Earth.

The bad news: A million other potentially dangerous -- and unknown -- city-killing space rocks are out there, and one of them could be on a collision course with Earth.

"It's like Mother Nature sending a warning shot across our bow," said Don Yeomans, who tracks asteroids for the Jet Propulsion Laboratory in Pasadena, Calif.

Satellite operators said they were monitoring the asteroid but that they expected it to safely cruise through a belt of satellites some 23,000 miles up.

"We're watching the situation but there's not a giant concern," said Alex Horwitz, spokesman for Intelsat, which operates some 50 communications satellites.

The Air Force, meanwhile, is leaving the tracking to NASA.

An astronomer in Spain spied the asteroid a year ago. Small, dim and speedy, it was a "slippery target" as it moved across a background of stars, said Jaime Nomen of the La Sagra Observatory in southern Spain.

NASA-funded scientists then ran the numbers: The asteroid was about 150 feet wide. Its closest approach will occur at 2:24 p.m. EST on the 15th. On the night side of the planet -- mainly Asia and Australia -- observers with small telescopes might see a pinpoint streaking at the rapid clip of two moon-widths per minute.

Further observations refined the asteroid's path. It cruises around the sun in an orbit almost identical to Earth's. Our year is 365 days. Its year is a day longer. Like a drunk driver weaving across lanes, asteroid 2012 DA14 crosses paths with Earth twice a year at varying distances.

Despite these opportunities for disaster, scientists tracking the asteroid are confident 2012 DA14 won't collide with us for at least the next century, which is as far as they've been able to project its path. Next week's approach is the closest during that time.

NASA began rigorously scanning the sky for cosmic hazards only in 1998, when Congress told them to. Agency scientists said Thursday they are confident their network of ground and space telescopes have found at least 95 percent of potentially planet-killing asteroids, those a half-mile wide or more. None of these monsters is headed toward Earth, Yeomans said.