[meteorite-list] Russian Meteor Not Associated With Asteroid 2012 DA14

[Ron Baalke]

http://www.jpl.nasa.gov/news/news.php?release=2013-061

Russian Meteor Not Associated With Asteroid 2012 DA14
Jet Propulsion Laboratory
February 15, 2013

Preliminary information indicates that the fireball in Chelyabinsk, 
Russia, is not related to asteroid 2012 DA14, which is flying by Earth 
today.

The Russian fireball is the largest reported fireball since the 1908 
Tunguska event. The fireball entered the atmosphere at 18 km per second. 
The impact time was 3:20:26 UTC, and the energy released by the impact 
was in the hundreds of kilotons. Based on the duration of the event, it 
was a very shallow entry. It was larger than the fireball over Ind
onesia on Oct. 8, 2009. Measurements are still coming in, and a more 
precise measure of the energy may be available later. The size of the 
object before hitting the atmosphere was about 15 meters, the pre-impacting 
asteroid was about 15 meters in diameter and had a mass of about 7,000 tons. 
It was about 1/4 the size of asteroid 2012 DA14. The fireball trail was 
visible for about 30 seconds, so it was a grazing impact through the 
atmosphere. The fireball was brighter than the sun.

It is important to note that this estimate is preliminary, and some of the 
estimates may be revised as more data is obtained.

http://www.nasa.gov/topics/solarsystem/features/asteroidflyby.html