Wednesday, March 20, 2013

Unexpected meteor on way? 'Pray,' says NASA chief


When an unexpected visitor comes crashing into Earth with the force of 20 atomic bombs, Congress sits up and notices. And then schedules a meeting.

The House of Representatives heard testimony Tuesday about the meteor that surprised the world Feb. 15 when it lit up the Russian sky with the light of a thousand suns.

Neither the head of NASA nor the commander of the Air Force Space Command had comforting words for the congressmen.

Rep. Bill Posey (R-Fla.) asked what NASA director Charles F. Bolden Jr. what the space agency could do if, with only three weeks notice, a large asteroid was heading on a collision course with our planet.

"Pray,'" Bolden said ...


 Read the full story (and comments) by Sam Wood  in PHILLY.com


• CBS News: NASA's advice for near-term meteor strike: "Pray"


At a House Committee hearing Tuesday, NASA administrator Charles Bolden Jr. was asked what America would do if a meteor similar to the one that hit in Russia on Feb. 15 was found to be on a path toward New York City, with impact three weeks away. His response? "Pray."

At the moment, we might be lucky to get even three weeks warning. The United States and the rest of the world simply do not have the ability to detect many "small" meteors like the one that exploded over Russia, which has been estimated at roughly 55 feet long. Donald Yeomans, Manager of NASA's Near-Earth Object Program Office and the author of "Near-Earth Objects: Finding Them Before They Find Us," told CBSNews.com that there are a lot of these small meteors in orbit, and little early warning system in place to detect them.

Yeomans said the most efficient way to find them would be a space-based infrared telescope. This has two benefits: One, the sun would not serve to prevent detection of some objects, and two, the infrared nature of the telescope would mean it would be effective in detecting them. (Part of the reason there was no warning for the Russia meteor is that the sun blinded the satellites.) CBS News contributor and City University of New York physics professor Michio Kaku calls such a telescope a "no brainer," in part because it comes at the relatively low cost of a few hundred million dollars. 

"In Russia, if that asteroid had held intact for a few more seconds, it would have hit the ground with the force of 20 Hiroshima bombs," he said on CBS This Morning Tuesday, arguing the investment was worth it. Yeomans also called for ground-based wide field optical telescopes that could scan vast regions of the sky each night.

At Tuesday's hearing -- before the House Committee on Science, Space and Technology -- Gen. William Shelton, commander of the U.S. Air Force Space Command, acknowledged that the United States had no idea the Russian meteor was coming.

There is currently a project under way that would likely provide at least some warning for U.S. cities: The ATLAS, or Asteroid Terrestrial-Impact Last Alert System, is being developed to offer a one-week warning for a 148-foot meteor impact or a three-week warning for a 450-foot meteor impact. (The project, which involves eight telescopes, is scheduled for completion by the end of 2015.) Still, that's only enough time to evacuate residents and shore up infrastructure, not to head off the object entirely. 


The nation has done a far better job at tracking larger space threats than it has the smaller objects. 

"An object larger than one kilometer, which would cause a global problem -- we've found 95 percent of them already and none of them represent a problem in the next 100 years," said Yeomans. A hit from such an asteroid would be the equivalent of thousands of nuclear bombs going off, he said. "Civilization would survive probably, but not in the form that we know it." 

If such an object is discovered to be approaching Earth, the leading contender to address the problem would be to crash a spacecraft into it in order to slow it down and alter its course. "If you find it early enough, and you smack it early enough, you've got enough time," said Yeomans. The technology already exists to track and hit a space object: In 2005, NASA deliberately struck the Tempel 1 comet and photographed the impact. Still, for a large object, you'd need billions of dollars and, Yeomans estimates, at least a 10-year head start. 

"The technology is there, the question is do we have enough time to plan, build, launch and intercept these objects prior to an impact," he said. The good news is that, in the case of a large object approaching Earth, we would be expected to have decades of advanced warning ...   Read the full story (and comments) by Brian Montopoli  in CBS NEWS


• NASA asks for funding to hunt asteroids


The space agency says it needs more money to protect the planet by identifying near-Earth objects that could pose a threat ...  Read the full story by Stephanie Gosk  in Nightly News│NBC NEWS



No comments:

Post a Comment