Was the 1908 Tunguska Explosion an Electrical Event?

The Tunguska explosion of June 30, 1908, that devastated over 2000 square km of Siberian taiga has been attributed to the entry into the Earth\´s atmosphere of a fragment of comet or asteroid (Tunguska Cosmic Body or TCB) and its detonation at ~10km altitude.1 But after almost a century many enigmas remain. Why are there dozens of odd holes but no impact crater? Why are few meteoritic fragments found? What was the \´pillar of fire\´ reported to stretch from the ground to the bolide? One little-explored possibility is that the effects could be explained if the TCB were an electrically charged body.-\´" Powerful electrical discharges between the Earth, and a charged intruder could explain the "pillar of fire." The discharge could trigger internal dielectric breakdown and totally disrupt the TCB. This model offers a solution to the puzzle of comets exploding far from the Sun. Such an electrical explosion renders doubtful estimates of the size and nature of the TCB based on hypersonic shock disruption models. Electrical disruption could explain the melted and widely dispersed meteoritic micro-spherules found embedded in tree resin and peat bogs at the explosion site.4 Multiple electrical discharge scars are expected in the path of the TCB rather than a single impact crater. It is significant that a number of loud detonations were heard and dozens of small craters were discovered at the place of fall.6 Notably, scars on radially felled tree trunks were attributed to severe lightning accompanying the blast. And sounds reported to be contemporaneous with the fireball are consistent with electrophonic meteors. With the discovery of fresh craters on Mars7, their \´ejecta\´ patterns might usefully be viewed from an electrical viewpoint and compared with the Tunguska event. The implications of the electrical model for global extinction scenarios in terms of mechanical impacts are discussed.