Why is the far side of the moon so weird? Scientists may have solved a lunar mystery

Nov 25, 2019
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They haven't really 'solved' the mystery, they've just replaced it with another: the asymmetry may be due to KREEP-enriched material on the near side, but even if that's correct, we're left with "why is the near side enriched in KREEP?"
 
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Jun 1, 2020
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The view that the Theia produced two moons that became our Moon is nicely presented in a new book that I just finished reading, "When the Earth Had Two Moons", Erik Asphaug.
 
Jan 21, 2020
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Isn't the near side of the Moon more cratered than the far side simply because of explosion debris that was flung at the Moon on, say, the second twirl of the new Earth just after the Moon had been catapulted away? Or many more twirls of the turbulent Earth that needed quite a time to settle down before it stopped swirling a lot of matter into space? The far side of the Moon would not have been impacted by it as much. Or is my assumption wrong?
 
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Nov 18, 2019
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Aligns well w/ YeC creation science alt.
Yes from the Earth (reference the YeC SPIRAL's 'Draw-play' hypothesis.
Yes molten activity relatively recently, (and not that long ago).
Per 'Draw-play' one side of the moon was from closer to the Earth's surface so the other side from deeper-in the proto-Earth.
Also relatively low gravity moon and lack of time lapse (under 6k years) would mean not that many impacts if not those deflected by the Earth atmosphere and magnetic shield and or drawn to the area by the stronger gravitational pull of Earth along with larger objects that did hit the Earth, and or ejected from Earth then caught and/ or deflected to the side of the moon facing us.
 
Nov 18, 2019
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They haven't really 'solved' the mystery, they've just replaced it with another: the asymmetry may be due to KREEP-enriched material on the near side, but even if that's correct, we're left with "why is the near side enriched in KREEP?"
i think they imply because when the moon was part of the Earth , The Earth is not uniform, so perhaps what was from deeper had more (or less ) of x , that which was from nearer to our proto-surface the opposite.. See SPIRAL 'Draw-play ' lunar formation hypothesis.
 
Jun 27, 2020
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Isn't the near side of the Moon more cratered than the far side simply because of explosion debris that was flung at the Moon on, say, the second twirl of the new Earth just after the Moon had been catapulted away? Or many more twirls of the turbulent Earth that needed quite a time to settle down before it stopped swirling a lot of matter into space? The far side of the Moon would not have been impacted by it as much. Or is my assumption wrong?
Idnk, but would the moon be ideally locked so soon after the impact? For your scenario, it would have to be locked.
 
Apr 18, 2020
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"maria, or craters caused by volcanic activity on the moon."

I thought that maria were relatively smooth areas, characterized by a lack of craters ...
 
This find could tie in with recent finds of impactor remains in the Moon rocks, more the deeper you go, meaning Moon may be insufficiently mixed. "Regional rather than global early lunar crust building: Our results challenge the notion that crust-building magmatism that immediately followed the LMO was a Moon-wide event. The combination of radiogenic heat production and the ability of KREEP to lower the melting point of Mg-suite source rocks, as demonstrated here, would have led to considerably more crust-building magmatism under the nearside relative to the farside."
 
They haven't really 'solved' the mystery, they've just replaced it with another: the asymmetry may be due to KREEP-enriched material on the near side, but even if that's correct, we're left with "why is the near side enriched in KREEP?"
The paper wasn't aimed at that but looking at KREEP melts. "The Moon's Earth-facing hemisphere hosts a geochemically anomalous region, the Procellarum KREEP Terrane, which is widely thought to have provided radiogenic heat for mantle melting from ~3.9 to ~1 billion years ago. However, there is no agreement on such a link between this region and the earliest pulse of post-differentiation crust-building magmatism on the Moon at ~4.37 billion years ago; whether this early magmatism was global or regional has been debated."
 
Isn't the near side of the Moon more cratered than the far side simply because of explosion debris that was flung at the Moon on, say, the second twirl of the new Earth just after the Moon had been catapulted away? Or many more twirls of the turbulent Earth that needed quite a time to settle down before it stopped swirling a lot of matter into space? The far side of the Moon would not have been impacted by it as much. Or is my assumption wrong?

Idnk, but would the moon be ideally locked so soon after the impact? For your scenario, it would have to be locked.
"maria, or craters caused by volcanic activity on the moon."



I thought that maria were relatively smooth areas, characterized by a lack of craters ...

The main formation model is that the Theia impactor ejected mainly Earth mantle material (but now they seem to have seen some Theia remnants as well) into a debris disk, which fairly rapidly (within 1 kyrs) accreted to Moon. It was therefore molten, nearby orbiting and not tidal locked at the beginning - though both the distance and the absence of tidal lock changed quickly.

One hypothesis I've seen was that an early tidal lock would have subjected the nearside to a heat flow from Earth. But we now know the crust of large bodies forms quickly, so the heat flow must die quickly and the mares formed hundreds of millions years after Moon formation. Local radioactivity seems more viable, however the material were concentrated.

What this result do is to tie the observations of once radioactive KREEP with the mares (with the explanation of some volcanic craters as a bonus). It also simplifies the asymmetry to a regional one, which means it should be easier to derive the causes of.
 

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