Assuming the Earth’s surface has been broken apart by parasitic aliens, via a closely-meshed network of hatchlings interwoven into the crust itself (I know this is very specific, but please bear with me).
And assuming these hatchlings broke the Earth through kinetic force alone - no explosions, no epic lasers, etc.
AND ASSUMING these shattered pieces are now orbiting around another mass…
Will they be safe to roam around on? If they’re hot after the initial blast, how long will it take for them to cool down enough to be safe?
Finally, what will happen to the core of the planet afterwards?
If someone could answer my questions, I would really appreciate it.
The Earth, or rather proto-Earth, being shattered by a collision with Theia (whose core merged with Earth’s) is one of the leading hypotheses for the origins of the Moon. Afterwards a the surface of the moon was a magma ocean, or alternatively a magma ‘mush’, which would be decidedly dodgy ground to walk on.
If you are Kryptonian pieces of shattered planet are incredibly unsafe, of course.
If you magically break off pieces of the earth and move them somewhere else, you just have a bunch of rocks and they’re safe in the sense that a bunch of rocks floating in orbit are safe. The process of breaking up the earth will, in practice, involve a lot of heat since you’ll need a huge amount of energy to move any significant mass from the earth out of the gravity well and into orbit around another body - just look at how much fuel you you have burn to put a tiny Apollo lander on the moon - and using that energy will produce a lot of waste heat. How hot and how much cooldown time depend on factors you haven’t specified.
Really, if you have biological hatchlings in numbers/size enough to break off a significant portion (or all) of the Earth’s crust, and especially if they can generate enough energy to move that rock to another planet, you’re already outside of hard science territory, so you may as well make things act in the way that tells the best story.
I’ve handled chunks of the shattered Earth plenty of times. A few of them have sharp edges that you need to be careful of, and some are heavy enough to hurt if you drop them on your foot, but other than that, they’re safe.
That all depends on WHERE they are ? If they are in a cloud that is only a few times larger than the present earth, the hot insides of the earth would remain hot…
It greatly depends on what those shattered pieces are. If they’re parts of the crust or even mantle, and have cooled, then they should be fine. How long it takes them to cool is very dependent on the size of the fragments.
The core fragments, I’m not so sure about…that shit’s radioactive.
Most chunks would be cool enough to touch within a matter of days. It’s like how a volcanic lava flow forms a rocky outer crust even if the center is still molten.
Your bigger pieces, including the core, might have enough currents and convection going on that the crust is regularly broken up, pulled under, etc. which would keep the surface hotter for longer. And the larger amount of heat would keep the crust hotter as well, but the Earth itself is a good example: only the two few kilometers of the Earth is safe enough to touch. It’s a pretty short distance down until you can boil water on the rocks, so an object with a very high average temperature can still have a cool/cold crust on top of it.
The Earth’s core is not only dealing with residual heat, but also heat generated through radioactive decay. The heavier and metallic elements tended to migrate to the core. So the core would remain hot for a very, very long time. Even having blasted off the outside layers, my guess is that a residual core would still be molten billions of years from now. the cooled surface of that core would favor the lighter elements, but it would certainly be more metallic than the Earth’s current crust. You’d also see higher gravity at the surface of that residual core, thanks to a higher average density in the remnant.
I think Grimalkin is asking about the removal of the crust, leaving the mantle and the core intact. Although this would release a lot of energy as waste heat, the top of the mantle would cool fairly soon (a few thousand years, depending how efficient the parasites were at lifting the crust) and become just the surface of a lifeless, ugly planet.
The chunks of crust would become asteroids, orbiting the mysterious other body mentioned in the OP; these would be safe to ‘touch’, but would be irregular in shape and have a very low gravity and no air or life. Don’t expect to be able to walk about on them safely without a spacesuit, and be prepared for extreme acrobatics as you try not to reach escape velocity with every step.