Possible exposure of Earth to dense interstellar medium 2-3M years ago

Post by delichon » Tue, Jun 11, 2024, 3:44 AM UTC

animaomnium wrote: post #4

Very interesting paper! Proposes (with lower bound of 1.3% chance) that the solar system may have passed through a local interstellar cloud, which would have caused the heliosphere to shrink to smaller than the orbit of the earth (0.22 au) some 2-3 mya. This may have affected the Earth's atmosphere and climate. Scroll down for some cool illustrations of a simulation showing how the heliosphere would have been tiny wi…

Post by gerad » Tue, Jun 11, 2024, 4:36 AM UTC

delichon wrote: post #21

animaomnium wrote: post #4

Very interesting paper! Proposes (with lower bound of 1.3% chance) that the solar system may have passed through a local interstellar cloud, which would have caused the heliosphere to shrink to smaller than the orbit of the earth (0.22 au) some 2-3 mya. This may have affected the Earth's atmosphere and climate. Scroll down for some cool illustrations of a simulation showing how the heliosphere would have been tiny wi…

> This may have affected the Earth's atmosphere and climate. Adding uncertainty to climate forecasting models. Can we detect or predict changes to the interstellar medium in our path through space and improve forecasts with that? Maybe we could at least put an upper bound on the magnitude of the effect.

Post by shiroiushi » Tue, Jun 11, 2024, 4:50 AM UTC

bloopernova wrote: post #17

shiroiushi wrote: post #16

Earlier quoted context omitted.

Remember, modern humans appeared around 1.5-2M years ago, so this event, geologically speaking, happened shortly before the arrival of modern humans. Perhaps this event had something to do with us evolving.

Do you mean Homo Erectus or Homo Sapiens? Sapiens arrived around 300k years ago, according to Wikipedia. Erectus did indeed arrive around 2M years ago. https://en.wikipedia.org/wiki/Human https://en.wikipedia.org/wiki/Homo_erectus

Post by imiric » Tue, Jun 11, 2024, 5:31 AM UTC

barfbagginus wrote: post #10

Why does this make me feel a little dirty and exposed ? Like, who knows what kinda alien DNA strands or spores are carried by the ISM?! I wonder if it would be possible to track biodiversity increases caused by the transit? Assuming there is biological material in the ISM, perhaps some of it made it into our biosphere! Very fun!

Post by s1artibartfast » Tue, Jun 11, 2024, 5:36 AM UTC

bloopernova wrote: post #7

Are we able to determine if other star systems have experienced the same type of encounter? (Not statistically, I mean detection or instrument based) I'm assuming it's either difficult or impossible to measure another star's heliopause. It would be fascinating to see the effects of a cold cloud interaction in "real" time!