5 Kt Meteor Blast over California

From: http://www.nationalufocenter.com/artman/publish/article_453.php

NASA's Goddard Space Flight Center and Astrophysical Journal,
 A sonic boom heard in California last week had an out-of-this world origin as ”a large meteoric event” according to NASA’s Meteoroid Environment Office. Scientists now estimate the blast measured in near 5 kilotons or roughly 1/3 the power of the atomic bomb dropped on Hiroshima, Japan during World War II. Bill Cooke of the Meteoroid Environment Office at NASA’s Marshall Space Flight Center, estimates the object was about the size of a minivan, and weighed in at around 154,300 pounds.

"Most meteors you see in the night’s sky are the size of tiny stones or even grains of sand and their trail lasts all of a second or two," said Don Yeomans of NASA’s Near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, California. “Large meteors can be seen in the daytime and are many times that size – anywhere from a baseball-sized object to something as big as a minivan.”  The meteor appears to be much more valuable than scientists first thought. Meteorite hunters found fragments of the rock, identified by the "fusion crust" that forms when it burns in the atmosphere. NASA and the SETI Institute in Mountain View, California, also mobilized a search team of about 30 scientists to search for the small black rocks. The meteorite turned out to be a very rare type of rock called CM chondrite, which makes up less than 1 per cent of the meteorites that fall to Earth. According to Bill Cooke of NASA's Meteoroid Environment Office at the Marshall Space Flight Center in Huntsville, Alabama, it is not clear whether it is rare because it easily burns up in the atmosphere or there are just fewer of these rocks in space.