On June 30th, 1908, something exploded over Tunguska, in central Siberia. Over the last ninety years this catastrophic event has inspired a plethora of scientific investigations. Despite many interesting findings, there are still substantial open questions and inconsistencies among the theories and the available data (for a review see Vasilyev 1998).
Among many different effects, the Tunguska explosion produced shock waves, which were recorded by seismographs at several sites. Ben-Menahem (1975) made a detailed analysis of these seismic records and derived an explosive energy of Mton. He also concluded that the data on the energy source are consistent with an airburst at a height of about 8.5 km.
In a previous letter (1998), we have shown that seismic data can be used to characterize the very bright 1993 Lugo bolide, obtaining a good match between the derived solution and the observations. Here the same methodology is applied to analyze the Tunguska event, using Ben-Menahem's analysis as a starting point.
© European Southern Observatory (ESO) 1999
Online publication: December 22, 1998