On Fri, May 29, 2015 at 10:08 AM, Georgi Guninski
Well — yes. In modern times, of course. bomb exploded at Alamogordo was the first one to be detonated, as quoted in Doomsday, 1999 A.D. (1982) by Charles Berlitz, p. 129
This came up in searches for ``ancient nuclear wars india''
http://ancientnuclearwar.com/ https://theextinctionprotocol.wordpress.com/2011/07/20/historys-lost-lesson-... Another timescale is the rendering and destruction of evidence of civilization living on or in any mutable surface or layer by natural geologic / cosmic processes, yet within time sufficient for another to develop. Poor links but you get the idea. http://en.wikipedia.org/wiki/Fossil http://en.wikipedia.org/wiki/Archean http://en.wikipedia.org/wiki/Weathering