More information is coming to light regarding the large bolide meteor believed to have exploded in the atmosphere over Reno, Nevada and the Sierra Mountain Range of California early on Sunday morning, April 22, 2012.
According to respected scientific web site SpaceWeather.com , the loud, concussive explosion caused by the meteor impacting Earth's atmosphere, rattled homes and was heard in a broad area covering more than a thousand square miles. The explosion caused a flurry of calls to emergency services from concerned citizens across the region.
According to Bill Cooke, head of NASA's Meteoroid Environment Office, the source of the blast was a moderate meteor roughly the size of a minivan. "The energy is estimated at a whopping 3.8 kilotons of TNT, so this was a big event," Cooke states. "I am not saying there was a 3.8 kiloton explosion on the ground in California. I am saying that the meteor possessed this amount of energy before it broke apart in the atmosphere." 3.8 kilotons would be approximately one fourth of the energy released by the "Little Boy" atomic weapon dropped on Hiroshima, Japan, at the end of WWII.
As for the conjecture that this bolide meteor event was a part of the yearly Lyrid meteor shower, Cooke is not convinced: "This meteor was probably not a Lyrid; without a trajectory, I cannot rule out a Lyrid origin, but I think it likely that it was a background or sporadic meteor." The Lyrid meteor shower is believed to be the remnants of Comet Thatcher, which disintegrated as it neared the sun.