About The Cosmic Clock, the Cycle of Terrestrial Mass Extinctions
The Cosmic Clock, the Cycle of Terrestrial Mass Extinctions- Paper by J. A. Marusek. A dual cycle of extinction events is observed and well ordered in geological time. Two primary mechanisms, Oort cloud comet impacts and nearby supernova events are synchronized to the passage of the solar system through the spiral arms of the Milky Way galaxy.
