The 1908 Tunguska event: analysis of eyewitness accounts of luminous phenomena collected in 1908

Historically there were two main reasons to assign the 1908 Tunguska event to a spacebody infall: a) newspaper notes about a fall of a meteorite near the town of Kansk (later claimed to be false); b) eyewitnesses reports about seeing luminous phenomena in the sky. This paper examines accounts of the Siberian eyewitnesses about luminous phenomena in the sky, collected in 1908, immediately after the event. The conducted generalization of the available accounts reported in 1908 indicates that eyewitnesses reported several types of luminous phenomena.