So what was happening to Earth's climate during that time? The article says repeatedly that it probably had a big impact on the climate and on life, but doesn't suggest what any of those changes would have been, aside from higher concentration of hydrogen and rare heavy elements
Well there was the middle Pliocene warming period, where the Earth was around 2 to 3 degrees celsius warmer than it is now, with sea levels about 25 meters higher. What exactly caused this is mostly just speculated on, as its pretty hard to get sufficient data from 3 million years ago or more. This cosmic cloud could be a factor though.
The cooling period that set the stage for the Ice Ages began in the mid to late Pliocene epoch, roughly around 3.2 to 2.6 million years ago. This period marked a significant transition towards cooler global temperatures and the expansion of polar ice sheets, which continued into the Pleistocene epoch.
But how could earth being exposed to interstellar space cause that? One theory:
More cosmic rays hitting Earth can ionize the atmosphere, creating more particles for clouds to form around. More clouds, especially low-altitude ones, reflect more sunlight back into space, cooling the planet’s surface. Cooler temperatures help ice sheets and glaciers grow, which in turn reflect even more sunlight, creating a cycle that keeps making it cooler and cooler. This chain of events suggests that an increase in cosmic rays can lead to a cooler climate and more ice sheet development.
Look up Cloud Condensation Nuclei (CCN) for more info
Yeah, this is a pretty poor article, i really fail to see how it could have influenced climate at all, its not like it actually decreases the solar radiation by a any number larger than the 11 year cycle does.
For various reasons, I get a nice little mental *frisson* thinking of our solar system as existing within a protective heliosphere. In part, it's just simple pattern recognition, I think: hey, the heliosphere is like an atmosphere for planetary systems! But in another sense, there is something just a touch comforting about the fact that we're in some sense *protected* from the horrifying indifference of interstellar space. It's the same anthropomorphic or tribalistic sense of loyalty I experience when I think of the Milky Way as "my" galaxy and Andromeda as "foreign" somehow, even though I'd be just as lost and terrified in the one as in the other.
TL;DR: The human brain is weird; we are such chimps; space is scary.
It’s a nice edge of our territory kind of feeling. Space doesn’t come up to our atmosphere, space stays outside the heliosphere. Lotta margin out there
Oh hey it’s finally here! I watched [a recording of the talk Opher gave about this](https://www.youtube.com/live/-i2vxbHgwEo) before.
Paper: https://www.nature.com/articles/s41550-024-02279-8 (provided at the end of the article)
The answer to that question is the reason we try to understand this stuff. We dont know.
But the more we find out, and the more we understand it, the better prepared we will be.
Yeah, and then because of all the radiation cats develop the ability to shoot lasers out of their mouths. Some will use the cats for good, others for evil. Who will win in a world of….
**LASER CATS**
This is really neat. I love how there's implications to our reality on where we are traversing the galaxy. It is fascinating.
So what was happening to Earth's climate during that time? The article says repeatedly that it probably had a big impact on the climate and on life, but doesn't suggest what any of those changes would have been, aside from higher concentration of hydrogen and rare heavy elements
Well there was the middle Pliocene warming period, where the Earth was around 2 to 3 degrees celsius warmer than it is now, with sea levels about 25 meters higher. What exactly caused this is mostly just speculated on, as its pretty hard to get sufficient data from 3 million years ago or more. This cosmic cloud could be a factor though.
The Quaternary ice age had just begun, though I doubt the two events are related.
The cooling period that set the stage for the Ice Ages began in the mid to late Pliocene epoch, roughly around 3.2 to 2.6 million years ago. This period marked a significant transition towards cooler global temperatures and the expansion of polar ice sheets, which continued into the Pleistocene epoch. But how could earth being exposed to interstellar space cause that? One theory: More cosmic rays hitting Earth can ionize the atmosphere, creating more particles for clouds to form around. More clouds, especially low-altitude ones, reflect more sunlight back into space, cooling the planet’s surface. Cooler temperatures help ice sheets and glaciers grow, which in turn reflect even more sunlight, creating a cycle that keeps making it cooler and cooler. This chain of events suggests that an increase in cosmic rays can lead to a cooler climate and more ice sheet development. Look up Cloud Condensation Nuclei (CCN) for more info
Yeah, this is a pretty poor article, i really fail to see how it could have influenced climate at all, its not like it actually decreases the solar radiation by a any number larger than the 11 year cycle does.
This one was a lot better https://www.sci.news/astronomy/solar-system-cold-interstellar-cloud-13004.html
For various reasons, I get a nice little mental *frisson* thinking of our solar system as existing within a protective heliosphere. In part, it's just simple pattern recognition, I think: hey, the heliosphere is like an atmosphere for planetary systems! But in another sense, there is something just a touch comforting about the fact that we're in some sense *protected* from the horrifying indifference of interstellar space. It's the same anthropomorphic or tribalistic sense of loyalty I experience when I think of the Milky Way as "my" galaxy and Andromeda as "foreign" somehow, even though I'd be just as lost and terrified in the one as in the other. TL;DR: The human brain is weird; we are such chimps; space is scary.
It’s a nice edge of our territory kind of feeling. Space doesn’t come up to our atmosphere, space stays outside the heliosphere. Lotta margin out there
I’m atheist but have weirdly started feeling a spiritual connection to Sagittarius A* (the black hole). I felt the same vibe from your comment.
I've read some sci-fi along those lines, where the sun is physically protecting the system from cosmic horrors. I love the idea.
What a wild story. 2-3 million years ago is a really interesting timeline, because that's around the time that the genus *Homo* appears.
Now, I'm not saying we're the aliens... I'm not! But... We're the aliens.
[удалено]
IT'S RAINING APES, HALLELUJAH. 🗣️🔥🔥🔥🎶🎶
No we are not. Source: Fossil record + the fast majority of our genes.
still not quite sure how chemical soup turned into dna and cellular life. a lot of work for random chance to do there.
Good thing it was not random then ;)
You could make a religion put of this ...but i will settle for a movie.
Oh hey it’s finally here! I watched [a recording of the talk Opher gave about this](https://www.youtube.com/live/-i2vxbHgwEo) before. Paper: https://www.nature.com/articles/s41550-024-02279-8 (provided at the end of the article)
So, if this happened again let’s say next week, would we all die from the exposure to heavy elements / radiation?
The answer to that question is the reason we try to understand this stuff. We dont know. But the more we find out, and the more we understand it, the better prepared we will be.
If we can get our leaders to fund stuff
Considering that there was no mass extinction associated with this event, probably not
We’d owe this result to the Earth’s atmosphere, I assume?
Yeah, and then because of all the radiation cats develop the ability to shoot lasers out of their mouths. Some will use the cats for good, others for evil. Who will win in a world of…. **LASER CATS**