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Nathan Myers

There should be something like 50K stars within 50 parsecs of us, which should have produced maybe 3 supernovae in 3M years. They can't have drifted far in only 0.01 galactic rotations. Shouldn't we have some very good guesses as to which nearby supernova remnant donated all that 60Fe to our biome? And, shouldn't 60Fe's decay rate enable us to date it precisely?

Apparently supernova remnants last only around 100K years, so ours is long gone. The resulting pulsar should last 100x longer, but they don't loiter about. The nearest of roughly the right age is PSR 1856−3754, 3.76M years old and 161 ps off, but it must have popped more than 1000 ps away. Ours, that must have terrified (or inspired?) Australopithecus africanus, has since fled the neighborhood. Arguably it should be identifiable by its high red-shift and small proper motion, but I haven't found evidence of anybody looking, yet.


We have much newer pulsars that must have popped nearby. PSRJ 0659+1414 is only 111K years old and 290 ps away. Since it blew, it can't have gone more than 44 ps, and maybe much less. PSRJ 0633+1746 is 342Kyo and 156 ps away. It's less than 140 ps away from its birthplace.

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