Wed February 19, 2014
Earth's "Close Calls" With Asteroids Depend On Who You Talk To
An asteroid estimated to be three football fields in diameter flew by Earth earlier this week, missing our planet by “only” two million miles while traveling at roughly 27,000 miles per hour. Many consider the two million mile cushion a “close call.” Wayne Wooten, an astronomer at Pensacola State College, is not among them.
“Really far away,” says Wooten. “I think why this one got publicity when we actually had a bigger one come a lot closer just three or four days earlier was because it had been lost and then recovered. But this is not too unusual. These are small bodies.”
The asteroid that zoomed past on the other side of the Moon, says Wooten, posed no major threat. The first asteroids of 2014 come almost a year after a relatively small asteroid – about 60 feet across - exploded over Chelyabinsk, Russia with the force of about 30 early nuclear bombs. The blast from that asteroid left more than 15 hundred people injured, mostly by glass from shattered windows, and raised concerns about the threat that stray asteroids present.
The B-612 Foundation is a private effort to launch a space telescope that could find smaller asteroids. Their proposed telescope, called Sentinel, is intended to find asteroids up to 450 feet wide. The mission is said to carry a 450 million cost — 250 million to build the spacecraft and 200 million to operate it for a decade.
Wooten says that scientists at NASA – and elsewhere -- are getting better at tracking asteroids.
“We now have had two cases of asteroids that we did see coming and they impacted exactly where we expected them to,” Wooten says. “On time, back in 2008 and the first day of this year. We had a little fella that hit in the middle of the Atlantic Ocean. Nobody actually saw it hit, but we had enough data that we’re pretty sure that’s where it hit.”
Meanwhile, the International Space Station and its crew theoretically are in the line of fire when it comes to asteroids nearing Earth. But Wayne Wooten at PSC says asteroids take a back seat to all the man-made space junk up there.
A group of experts on near-Earth objects – NEOs -- met in Vienna earlier this month. Among the topics discussed was establishing an International Asteroid Warning Network -- considered a critical step in gathering and sharing information -- about potentially hazardous NEOs.