RT @michael_w_busch: I am reminded to remind everyone that the orbital lifetimes of objects on Earth-crossing orbits are of order a million…
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RT @MarkBoslough: Years later I got to visit the K/T boundary in Gubbio, Italy & a nearby rock quarry with Gene & Carolyn Shoemaker, A Mont…
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RT @michael_w_busch: I am reminded to remind everyone that the orbital lifetimes of objects on Earth-crossing orbits are of order a million…
4,077 followers
I am reminded to remind everyone that the orbital lifetimes of objects on Earth-crossing orbits are of order a million years; and so the impact rate on Earth can only change on that timescale or longer. Such as the Eocene episode 37-34 million years ago: