The Earth may have survived its close encounters with an asteroid and a meteor Friday, but the episodes focused new attention on gaps in astronomers' ability to identify smaller space rocks like these capable of inflicting widespread destruction.
Efforts to better identify those threats are underway, including a new space telescope from a Silicon Valley foundation, and a coordinated telescope system in Hawaii.
"We're carrying out the most ambitious interplanetary space mission ever. We're building a space telescope, we're going to find them and track them so we have decades of notice before another one of these hits," says Ed Lu, a former shuttle and International Space Station astronaut who heads the B612 Foundation. If it is able to raise $450 million, the scientists plan to launch a meteor-mapping satellite in 2017 or 2018.
Meanwhile, a team at the University of Hawaii is working on ATLAS: The Asteroid Terrestrial-Impact Last Alert System, with the aid of a $5 million grant from NASA. Using eight small telescopes, the asteroid detection system would scan the sky twice a night looking for objects moving through space. The plan is to have the system operational by the end of 2015. They predict their system could offer a one-week warning for a 50-yard diameter asteroid, or "city killer," and three weeks for a 150-yard-diameter "county killer."
"That's enough time to evacuate the area of people, take measures to protect buildings and other infrastructure, and be alert to a tsunami danger generated by ocean impacts," says John Tonry at the university's Institute for Astronomy.
The Russian meteor came as a surprise when it blazed across the sky Friday morning over Russia's Chelyabinsk region, 900 miles east of Moscow. NASA scientists estimated it was about the size of a school bus, between 30and 50 feet across, traveling at 40,000 mph.
Thankfully, most of the meteor burned up as it hit the atmosphere 15 miles up, says Bill Cooke, lead for the Meteoroid Environments Office at NASA's Marshall Space Flight Center in Huntsville, Ala. Although a few small pieces might have hit the ground, the friction of hitting the atmosphere turned it into the fireball that transfixed the world and produced an aerial blast as powerful as 20 Hiroshima bombs, according to Russian estimates. The shock wave produced by the meteor blew out windows in an estimated 4,000 buildings, injuring around 1,200 people, mostly with glass cuts.
The day's second visitor was asteroid 2012 DA14, which astronomers had been tracking for over a year. It was clear the 150-foot chunk of rock would skim by Earth. At its closest it was 17,100 miles above the planet.
USA Today
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