Happy Tunguska Day!

[Dave Monroe]

Tunguska Event

145; 764; 775; and time-travel effects of, 778-781; 782 784; 792,
passim; an explosion that occurred at 60°55′N 101°57′E, near the
Podkamennaya (Under Rock) Tunguska River in what is now Evenk
Autonomous Okrug, at 7:17 AM on June 30, 1908. The event is sometimes
referred to as the great Siberian explosion.

http://against-the-day.pynchonwiki.com/wiki/index.php?title=T