Global Rumblings: Brightest Meteor Yet Observed by NASA as of Jun 2, 2011

Saturday, June 18, 2011

Brightest Meteor Yet Observed by NASA as of Jun 2, 2011

Space.com
Thu, 02 Jun 2011 07:18 CDT

Man-size meteor lights up Georgia sky Brightest meteor yet recorded by NASA's fireball-observing network - 2nd June 2011

A brilliant meteor blazed through the sky above Georgia recently, and two NASA fireball-monitoring cameras caught the dramatic display on video.The meteor was caused by a human-size chunk of an unknown comet. It was the brightest meteor yet recorded by NASA's fireball-observing network — based at Marshall Space Flight Center in Huntsville, Ala. — in its nearly three years of operation, officials said.
The 6-foot-wide (1.8-meter) space rock barrelled into Earth's atmosphere at 10:47 p.m. EDT on May 20 (0247 GMT on May 21), about 66 miles (106 kilometers) above the city of Macon, Ga.

Two NASA all-sky cameras, both located in northwest Georgia, tracked the resulting meteor and captured it on video. Analysis of the videos allowed scientists to calculate the basics of the object's speed, trajectory, mass and orbit.
When it entered the atmosphere, the comet chunk was traveling northwest at about 86,000 mph (138,404 kph), researchers said. At this velocity, the boulder-size "dirty snowball" possessed an energy or striking power somewhere between 500 and 1,000 tons of TNT.

Comment: Oh, yeah, nothing to worry about, NASA tells us. We are always bombarded by man size meteors, they say, and it's just a coincidence that there are much more frequent and visible sightings above populated areas! But if our memory serves us well, until not so long ago we were told that such events happen only once in a while. Changing history and counting on public's short memory, anyone?

A robotic fireball-monitoring network

NASA's meteor-watching network, run by the Meteoroid Environment Office at Marshall, currently consists of four robotic cameras: the two in Georgia, one in Huntsville, and one in southern Tennessee. These "smart" cameras are linked into a computer system that automatically analyzes their video, then calculates relevant information about incoming space rocks' trajectories and orbits.

Researchers hope to place a total of 15 such cameras in various locations throughout the eastern United States, which has few such systems, NASA officials said.

The overall goal of the camera system is to learn much more about the pieces of space rock that strike Earth and our atmosphere - how big they are, what they're made of and where they come from, researchers have said.