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“The tennis racket theorem or intermediate axis theorem, is a kinetic phenomenon of classical mechanics which describes the movement of a rigid body with three distinct principal moments of inertia. It has also dubbed the Dzhanibekov effect, after Soviet cosmonaut Vladimir Dzhanibekov, who noticed one of the theorem's logical consequences whilst in space in 1985. Formally the effect had been known for at least 150 years, having been described by Louis Poinsot in 1834.” Wikipedia.

Would this affect the crust, or is it too spherical and spinning on its primary axis to flip? If not the crust, could it flip the core if it is shaped so that it is rotating on its intermediate axis? Or is the core too close to spherical and rotating around its primary access to cause the core to flip?

I am asking regarding the flipping of the magnetic poles and in regards to the “Noah Myth” in the Bible about a “great flood.”

Qmechanic
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Digcoal
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2 Answers2

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As you note, Earth is spherical (and already spinning on an axis). So, the three moments of inertia required for the Dzhanibekov Effect are not very distinct. Without some massive additional force suddenly being applied to Earth, it's not going to happen. The Dzhanibekov Effect does apply to some of our neighbours like asteroids and Pluto's moon Nix, for example.

With regard to magnetic pole flipping, geological records suggest this happens with some regularity and since it's a reversible process, it can also come close to happening but then revert. A threat occasioned by pole flipping would be strong solar radiation caused by puncturing of Earth's temporarily weakened magnetic field** by solar flares. Floods, not particularly expected.

You might the link below interesting. In contrast to your question it examines how abrupt sea change levels cause magnetic reversal.

https://www.osti.gov/servlets/purl/1004148

** the weakened protective magnetic field would allow for holes to be made in the ozone layer.

Wookie
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The weight distribution of earth is not very symmetric at all, especially when taking the polar ice caps and the core mantle into account. There are 2 huge mantle blobs known as Large Low-Velocity Provinces (LLVP). They are located at:

  • 1st blob is located beneath the Pacific Ocean.
  • 2nd blob is located under the African continent.
  • Both are twice the size of our moon.

Therefore it is highly likely that earth has flipped several times due to this instability. There are several Youtube videos on explaining this in detail. In addition there are many anthropological and archeological indications that that has happened many times in earths history. (I'm not going to list any of those references here,as they are readily available in large quantities a google search away.

enter image description here

It should also be clear that the inner core rotates (mostly) separately from the outer core and mantle ([2]). In addition it has been recently discovered that the inner core rotation have slowed down ([3]). Because of the fluidity and dynamics in rotation period of inner,vs surface, modelling a flip would be both very difficult and likely yield inaccurate results in terms of time-frame/duration of such an event.

However, both ancient texts and geological features seem to indicate that the surface effects of such a flip could happen in a very short period of 1-5 days, with catastrophic and/or near-extinction level type of global floods and tsunamis. The oceans would be relatively sloshing around to adjust to crustal movements.

enter image description here

Reference:

not2qubit
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