Daily cosmobite: Tunguska 105th anniversary
In the early morning on this day in 1908 there was a colossal explosion in a remote area of Siberia near the Tunguska River with its effects noticed as far away as London. A small asteroid about 60 metres across is believed responsible.
Fallen trees were one of the signs of the Tunguska impact. Photo the Leonid Kulik expedition, courtesy Astronomy Picture of the Day