Poser about origin of Luna:

There is a new theory of Luna's origin: They hypothesize the very early Earth as having a very lightly held crust due to a faster rotation and the extreme heat of the early protoplanet that became Earth. The idea is that gravity barely held the crust together due to centrifugal forces and such and what happened is a georeactor, a natural fission reaction took place on a large enough scale to blast off a portion of the crust into orbit, creating the moon. The evidence, at least one line of evidence, is the rocks brought back by astronauts, the analysis of which shows the isotopic content to be identical to Earth crust. The idea there being the leading theory being a mars sized proto planet smashing into the Earth and blasting stuff into orbit to create the moon, they say that idea does not fly because the isotopic content of the resultant moon would be at least 20% something different from Earth but there is no such difference, thus they say that kills the impact theory. Fabian Fnas dis-agrees with this analysis, but however it happened, it certainly involved breaking off a huge chunk of Earth to make the moon, the isotope analysis proves that whether or not it happened like this new theory says.
So here is my poser:
Before this event happened, lets assume that the amount blasted away from the Earth was 2X the actual resultant mass of the present day moon, given that, what would have been the original size of Earth before this event and what would have been the surface gravity before the main event?

Originally posted by sonhouse
There is a new theory of Luna's origin: They hypothesize the very early Earth as having a very lightly held crust due to a faster rotation and the extreme heat of the early protoplanet that became Earth. The idea is that gravity barely held the crust together due to centrifugal forces and such and what happened is a georeactor, a natural fission reaction to ...[text shortened]... of Earth before this event and what would have been the surface gravity before the main event?

It's too easy. 🙂

Originally posted by coquette
It's too easy. 🙂

So easy, you aren't answering🙂

Originally posted by sonhouse
Fabian Fnas dis-agrees with this analysis, but however it happened, it certainly involved breaking off a huge chunk of Earth to make the moon, the isotope analysis proves that whether or not it happened like this new theory says.

And I still do.

Further, it's not a new theory, that a chunk of the Earth was thrown off of the crust to form the Moon. It says even that the lack of landmasses in the Pacific Ocean is the proof of the theory, because that's where the chunk came from. Look at the maps! However, this theory is older than the theory of tectonics. The fission mechanism is new, I'll give you that.

That has been a natural fission reactor in work. But it was far from explosive. I cannot think that any natural fission reactor has been explosive during the history of Earth.

I think it's much more plausible that the Moon was formed out of debris after a collision with a Mars-sized planet, early in Earth history. If this theory holds, the future will tell.

Originally posted by FabianFnas
And I still do.

Further, it's not a new theory, that a chunk of the Earth was thrown off of the crust to form the Moon. It says even that the lack of landmasses in the Pacific Ocean is the proof of the theory, because that's where the chunk came from. Look at the maps! However, this theory is older than the theory of tectonics. The fission mechanism is ...[text shortened]... ith a Mars-sized planet, early in Earth history. If this theory holds, the future will tell.

Well, in either event, I was asking the mass and diameter and surface gravity of Earth before the event, not verification of the various theories. I think it will be a lot clearer in maybe ten years when fine scale isotopic analysis is complete. If there was a reactor, it would leave isotopic evidence. The thing is, billions of years ago, there was a lot more plutonium, uranium, etc., that would have made such a fission affair more realistic as a theory. There is at least one known geo-reactor so the theory is not in left field. It must be ok, Kelly hasn't poo-poo'd it yet🙂