[meteorite-list] After Studying Russian Meteor Blast, Experts Get Set For Next Asteroid

[Ron Baalke]

http://cosmiclog.nbcnews.com/_news/2013/02/26/17105332-after-studying-russian-meteor-blast-experts-get-set-for-the-next-asteroid

After studying Russian meteor blast, experts get set for the next asteroid
By Alan Boyle
NBC News
February 26, 2013

The meteor that blew up over the Russian city of Chelyabinsk 11 days ago has 
provided a new focus for the international effort to deal with potentially 
threatening near-Earth objects, one of NASA's top experts on the issue says.

Lindley Johnson, the executive for the Near Earth Object Observation Program at 
NASA Headquarters in Washington, said that the Feb. 15 impact is certain 
to become "by far the best-documented meteor and meteorite in history" 
- but at the time, he and his colleagues could hardly believe it was happening.

"Our first reaction was, 'This can't be. ... This must be some test of a missile 
that's gone awry,'" Johnson told NBC News.

The Chelyabinsk meteor exploded at an estimated altitude of 12 miles (20 
kilometers) over the city of 1.1 million in Russia's Urals Mountains, setting 
off a shock wave that blew out windows, caused an estimated $33 million in 
property damage and injured more than 1,200 people.

It was doubly coincidental for Johnson and his colleagues: The meteor was thought 
to have been caused by the breakup of a 17-meter-wide (55-foot-wide), 10,000-ton 
asteroid that entered Earth's atmosphere and released the equivalent of 500 
kilotons of TNT in explosive energy. All this happened just hours before a 
45-meter-wide (150-foot-wide) asteroid, capable of setting off a city-killing 
blast, passed within 17,200 miles (27,680 kilometers) of our planet. Adding to 
that coincidence, researchers from around the world were gathered in Vienna 
for talks aimed at moving forward with an international network to deal 
with ... asteroid threats!

The spectacle in Russia "certainly brought renewed interest to our efforts here," 
Johnson said.

He said the recommendations from the researchers were "well-received" and are 
moving up the ladder to the next phase in a U.N.-led process for addressing 
outer-space threats. An action plan could be considered by the U.N. Committee 
on the Peaceful Uses of Outer Space during its next meeting in Vienna in June.

Johnson summarized the three main points of the recommendations:

 o Set up an international asteroid warning network, or IAWN, supported 
with existing detection assets but incorporating additional contributions. "The 
basis of such a network already exists," Johnson said, thanks to NASA, the 
European Space Agency, the International Astronomical Union's Minor Planet 
Center and the NEODyS asteroid-tracking center at the University of Pisa in 
Italy. NASA also has partnered with the U.S. Air Force to share tracking data 
about near-Earth objects. Just this week, a $25 million Canadian-built 
satellite known as NEOSSat was launched to look for small asteroids in 
Earth-threatening orbits.

 o Bring the world's space agencies together in a new working group called the 
Space Mission Planning and Advisory Group - also known as SMPAG (pronounced 
like "Same Page"). The group's purpose, Johnson said, would be to "get all the 
agencies on the 'same page' as far as assessing what capabilities could be 
brought to bear should there be a threatening asteroid detected."

 o Put asteroid experts in contact with countries around the world, to advise 
disaster response agencies about the nature of a potential impact event - that is, 
the area expected to be affected by the event, the potential impact and the scale 
of a potential evacuation. "It's an offshoot of the warning network," Johnson said. 
If the asteroid behind the Russian meteor had been detected in advance, for 
example, the expert network might have advised emergency workers about 
the potential for a midair blast and the resulting shock wave (although 
Johnson said he was "surprised" by the shock wave's effect).  Until last 
year, NASA spent about $4 million a year to track near-Earth objects, 
or NEOs, and Johnson said the program "has accomplished quite a bit in 
the relatively short time that it's been in existence." About 95 percent 
of the potentially threatening asteroids bigger than a kilometer (half-mile) 
wide have been detected. However, now NASA is working on charting the 
asteroids down to a width of 100 meters (330 feet). To fund that more 
difficult task, the annual funding level for NEO research was raised to 
$20 million a year.
 
NASA is using that money to beef up its capabilities for spotting smaller 
asteroids, through programs such as the Asteroid Terrestrial-impact Last Alert 
System, or ATLAS, which is due to get $5 million over the next five years. 
But less than a million dollars a year is going toward studies aimed at 
figuring out what to do if a threatening asteroid is found, Johnson  said. 
The potential strategies range from diverting it gently with the aid of 
gravity tractors or space paintball guns, to blasting it with nukes, Bruce 
Willis-style.

"It really depends on the scenario that we'd be faced with," Johnson said. 
"It depends on how big the object is. It depends on how long we have to do 
something about it. And if we do the search-and-detection job right, we will 
find a potential hazard many years if not decades before it becomes an 
immediate threat. There may be technologies available at that time that we 
never thought about. I don't get too worked up about trying to find an 
immediate technology tthat we've got to have right now to do that. Our focus 
is to find them as early as we can and have the maximum amount of time to 
do something about it."