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Network of stations with seismometers and air pressure sensors detected the blast waves A network of seismographic stations recorded spectacular signals from the blast waves of the meteor that landed near Chelyabinsk, Russia, as the waves crossed the United States. The National Science Foundation- (NSF) supported stations are used to study earthquakes and the Earth's deep interior. While thousands of earthquakes around the globe are recorded by seismometers in these stations--part of the permanent Global Seismographic Network (GSN) and EarthScope's temporary Transportable Array (TA)--signals from large meteor impacts are far less common. The meteor explosion near Chelyabinsk on Feb. 15,...

Current and planned efforts focus on larger objects Scientists have begun piecing together the characteristics of the meteor that exploded over Russia on the morning of February 15, using data from seismic instruments that track earthquakes and microphones designed to detect sonic booms from nuclear explosions. Unlike the asteroid DA14, which narrowly but predictably missed Earth later that day, the meteor was too small to detect before its contrail appeared in the dawn skies over the Russian city of Chelyabinsk. Yet even an object too small to detect can produce an impressive amount of destruction. The meteor was 15 meters...