16. Global View Relative DNA damage over about 2 years after a GRB
17. A GRB may have helped start the Late Ordovician Mass Extinction ~ 440 million years ago 2nd largest mass extinction known Primarily shallow-sea life at this time. No known land life.
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Notas do Editor
http://astrobio.net/news/modules.php?op=modload&name=News&file=article&sid=2443 Events: Tunguska on left, no deaths reported (but, animals). Dinos on right. Comet 12,900 years ago – may have killed megafauna and Clovis people in NAmerica
E values in energy released, not received. Normal solar output 100 billion megatons every second