Makes one wonder if the only reason we still have a liquid core is the mass injected deep under the mantle during the massive impact that formed the moon probably significantly heated a lot of the mass.
this post was submitted on 07 Sep 2025
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A fairly well accepted theory is that the moon's gravitational pull (tides) do a lot to churn earth's molten core, that churning adds heat and the mantle is a fantastic insulator. So all together, the moon is probably what's keeping our liquid core hot. (And in turn, the liquid core is probably what gives us our magnetic field. And the magnetic field is what keeps our atmosphere from blowing out into space. So that's all pretty important)
That tidal churn effect may also be why we have plate tectonics, which by the way is absolutely necessary to support life as we know it. Without plate tectonics, heavier elements would all sink to the center of the earth, but those churning plates are always bringing a mix of elements back up to the surface. And without some of those heavy elements, carbon based life wouldn't be possible. Also, technology wouldn't really be possible either, because if you think those rare earth metals are rare now, just imagine if they weren't found in earth's crust at all.
I think we have a lot to thank the moon for, it's probably the thing that does the most to make Earth a livable planet. Basically, if the Earth is special, the Moon is why.
More likely is the simple fact that Mars is closer in size and mass to The Moon, rather than The Earth
Mars is about twice the size of Earth's Moon which makes it half as volumous as earth. With that in mind it's not hard to imagine earth absorbing roughly a moons mass worth of hot angry rock would not increase the ambient temp in the core.
Yeah a lot of that impact energy is still retained as heat. Also it's though the collision that caused the moon was with an object about the size of Mars.
Astrophysics is a hobby. It is not my field but to my understanding it was a Mars ish size object and that's how we ended up with 2/3 of it folded into Earth and 1/3 plus some of Earths mass ejected into space to coalesce into the moon?
Mind you, I'm basing this off of some graphics I've seen and papers I've read years ago. Let me know if any of that sounds incorrect cuz I am not an authority.
Saw a short on that the other day. Current understanding is that the Earth's mantle formed the Moon and Theia formed Earth's core. Maybe it also brought water to Earth.
Do we think the giant 26km tall volcano had something to do with the core cooling completely?
It popped 😭
More likely is the fact that Mars is closer in size and mass to The Moon, rather than The Earth.
This probably kills any chance of terraforming Mars
The lack of a magnetic field was always going to prevent that, Musk was just a moron.
Eh, it’s a problem but my understanding is that atmospheric loss should be quite slow. The challenge of creating an atmosphere in the first place is nearly insurmountable but assuming we’re able to do that, there’s no reason it couldn’t be gradually replenished.
I mean we were never going to see the result of a complete terraform of Mars to begin with even if it went perfect with theoretical technology. I doubt our great great grandchildren would have seen it either. I was speculating on the long term. Flying colonies on Venus might be the best bet for long term 2nd human planet.
Agreed on all counts. Yeah, Mars was never really a good candidate for colonies, despite being technically the most earth-like planet.
Realistically, terraforming Mars would probably be something like a 3000 year project. But to me, that doesn't mean it's 3000 years away, it means it will actually never happen. Given the ever increasing pace of technology, I can't actually see a 3000 year project like that ever completing, because in that time the human race, and our goals would have changed immensely. We're already successfully editing plant and animal genomes, at some point we will have changed ourselves so much that the goal we aimed for a millennia ago no longer makes sense. We likely won't need an earth-like planet in the same way.
At any rate, I think space habitats are the way of the future, O'Neil cylinders and the like. Once you make it all the way to space, why trap yourself all the way down another gravity well?
"just give me a few hundred megatons of nuclear weapons and we can restart the core on Mars guys"
- melon husk, probably
Could an artificial field be created?
It would require more energy than we can produce at the moment.
What if we nuke something?
/s
There's is a video from 'Kurzgesagt' I think it was that explains why it's more realistic to settle Venus instead of Mars.
Edit: Found it
NASA's insight mission has discovered that Mars needs women.