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JustAPerspective t1_j61kq5f wrote

There's even supposition it may reverse direction, and researchers are looking for evidence of past impacts.

Thing is, humans didn't even know the core-as-a-core existed 60 years ago. They were still thinking that all the surface stuff was one big shell. So while it's fascinating to learn new things, figuring out what this means will take time.

And NOBODY knows for sure what's next. It's outside of our control, let's enjoy the mystery.

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Sharlinator t1_j6287vm wrote

“Reverse” as in start rotating slightly slower than the rest of the Earth, which I guess is “reversing” in a frame corotating with the planet. The same goes for “stopping”, those are really misleading terms to use because the core is very much rotating indeed at about one turn in 24 hours as expected! There’s absolutely nothing that could make it actually stop. Unfortunately, popular media is as clueless as always.

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Kenshkrix t1_j62fw1v wrote

>There’s absolutely nothing that could make it actually stop.

Nah the Earth's core could theoretically be stopped.

Just throw several moons/planetoids at it. The first one or two to blast the surface out of the way, the next to counteract most of the angular momentum, and maybe another one to really fine-tune things.

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Sharlinator t1_j62quod wrote

You’d have to be gentle enough not to blast away too much of the core in the process. so I’d think many, many smaller bodies over a longer period of time could work better.

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JustAPerspective t1_j63ge95 wrote

>There’s absolutely nothing that could make it actually
>
>stop
>
>.

The limits of human imagination in no way apply to reality.

Also, a magnetic engine can cease to function rather quickly when specific criteria change, so you may want to throttle back on "Absolutely".

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Sharlinator t1_j63i31s wrote

It’s not a “magnetic engine” in any relevant sense. It’s a huge rotating ball of iron and nickel and conservation of angular momentum is a thing! Truly ludicrous amounts of momentum would have to be transferred somewhere else for it to stop rotating.

(Now, to be fair, a mechanism does exist that slowly bleeds off Earth’s rotational momentum, and has done so for billions of years: the moon and its tidal forces. In the far future Earth would become tidally locked with the moon, and rotate very slowly, if the sun didn’t become a red giant first. But somehow only slowing down the core? That would require magic.)

Anyway, my use of “absolutely” should be taken in the context of the discussion, just like everything else. There’s no reason to add some sort of an “except via magic” to every other sentence, pedantic Redditors notwithstanding.

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JustAPerspective t1_j63vchz wrote

>It’s not a “magnetic engine” in any relevant sense.

Preposterous. Relevance is a matter of perspective; your prerequisite appears to be something along the lines of "if it ain't human-made it ain't real"?

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>It’s a huge rotating ball of iron and nickel and conservation of angular momentum is a thing! Truly ludicrous amounts of momentum would have to be transferred somewhere else for it to stop rotating.

...humans think.
See, until the 1960s, the existence of the core-as-a-core wasn't known. So the "obvious reality" you're assuming is younger than television.

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>(Now, to be fair, a mechanism does exist that slowly bleeds off Earth’s rotational momentum, and has done so for billions of years: the moon and its tidal forces. In the far future Earth would become tidally locked with the moon, and rotate very slowly, if the sun didn’t become a red giant first.)

Yes, that's how an engine operates on a timescale different from the ones humans focus on. You came that closet to getting the idea.

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> But somehow only slowing down the core? That would require magic.)

Magic is, by definition, merely reality: Magic is defined as a "supernatural force which influences reality" and "supernatural" merely means "attributed to some force beyond scientific understanding or the laws of nature" - and the "laws of nature" were written by humans who do not know everything.

See the one constant limitation here? Human understanding.

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>Anyway, my use of “absolutely” should be taken in the context of the discussion, just like everything else.

No - your use of a word will be taken at face value - the only use words have in true information exchange. If you are unable to use the words accurately or sincerely, that's your concern to manage.

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