[W4HM Spaceweather] Russian Meteor Update

[Thomas F Giella W4HM]

>From NASA.

RUSSIAN METEOR UPDATE: On Friday, February 15th at 9:30 am local time in 
Russia, a small asteroid struck the atmosphere over the city of Chelyabinsk 
and exploded. According to reports from news organizations and Russian 
authorit...ies, as many as 1000 people received minor injuries from the 
shock wave. This is the most energetic recorded meteor strike since the 
Tunguska impact of 1908.

Researchers have conducted a preliminary analysis of the event. "Here is 
what we know so far," says Bill Cooke, head of NASA's Meteoroid Environment 
Office. "The asteroid was about 15 meters in diameter and weighed 
approximately 7000 metric tons. It struck Earth's atmosphere at 40,000 mph 
(18 km/s) and broke apart about 12 to 15 miles (20 to 25 km) above Earth's 
surface. The energy of the resulting explosion was in the vicinity of 300 
kilotons of TNT."

"A shock wave propagated down and struck the city below, causing large 
numbers of windows to break, some walls to collapse, and minor damage 
throughout the city," he continued. "When you hear about injuries, those are 
undoubtedly due to the effects of the shock wave, not due to fragments 
striking the ground. There are undoubtedly fragments on the ground, but as 
of this time we know of no recovered fragments that we can verify."

Videos of the event may be found here and here. In many of the videos you 
can hear the sound of windows shattering as the meteor's loud shock wave 
reaches the ground. Onlookers cry out in Russian as alarms and sirens sound 
in the background. This pair of wide-angle gif animations is also worth 
watchin.

It is natural to wonder if this event has any connection to today's 
record-setting flyby of asteroid 2012 DA14. Paul Chodas of the Near Earth 
Object Program at JPL says no. "The Russian fireball is not related to 2012 
DA14 in any way. It's an incredible coincidence that we have had these two 
rare events in one day."

http://say26.com/meteorite-in-russia-all-videos-in-one-place


73 & GUD DX,
Thomas F. Giella W4HM
Lakeland, FL, USA
w4hm at tampabay.rr.com

W4HM Amateur Radio & SWL Autobiography: http://www.nz4o.com
W4HM Daily MF/HF/6M Radio Wave Propagation Forecast Subscription Service: 
http://www.solarcycle24.org
Lakeland, FL Daily Climatological Weather Data Archive: 
http://www.wcflunatall.com/nz4o22.htm