3.5 million years ago isn't that far away in geologic or even in
biologic time. I would think being irradiated by a kilonova would show
up a lot of other places besides a couple of isotopes in the crust.
Brent
On 12/12/2023 6:43 AM, John Clark wrote:
Surprisingly the isotopes Iron-60 and Plutonium-244 were found in
ocean sediments that are known to be between 3 and 4 million years
old, and no, the Plutonium couldn't have come from nuclear bomb
testing in the 1950s because nuclear bombs use Plutonium-239 not 244.
Pu-244 has a half-life of 81 million years and Iron-60 is 2.6 million,
so these elements must've been produced long after the Earth formed. A
supernova can produce Iron-60 but it is thought that only a kilonova,
the collision of two neutron stars, can produce plutonium-244. By
taking into consideration the known age of the ocean sediment and the
ratio of those two isotopes, a recent paper has calculated that those
results could be explained by a kilonova exploding about 550 light
years from Earth 3.5 million years ago.
Did a kilonova set off in our Galactic backyard 3.5 Myr ago?
<https://arxiv.org/pdf/2311.17159.pdf>
John K Clark
--
You received this message because you are subscribed to the Google
Groups "Everything List" group.
To unsubscribe from this group and stop receiving emails from it, send
an email to everything-list+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/everything-list/CAJPayv1wjXD9iDMUCnK6M3rG8fnppaau3pxBaBvGXcKbXYBnWg%40mail.gmail.com
<https://groups.google.com/d/msgid/everything-list/CAJPayv1wjXD9iDMUCnK6M3rG8fnppaau3pxBaBvGXcKbXYBnWg%40mail.gmail.com?utm_medium=email&utm_source=footer>.
--
You received this message because you are subscribed to the Google Groups
"Everything List" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to everything-list+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/everything-list/e6edcd25-4ca8-410a-86fa-9ebc7dd7df07%40gmail.com.
