The Moon’s nearside (left) is dominated by vast volcanic deposits, while the far side (right) has far fewer). Why the two sides are so different is an enduring lunar mystery. Credit: Brown University
Posted on 04/10/2022 8:00:07 PM PDT by BenLurkin
A new study published in the journal Science Advances shows that the impact that formed the Moon’s giant South Pole–Aitken (SPA) basin would have created a massive plume of heat that propagated through the lunar interior. That plume would have carried certain materials — a suite of rare-Earth and heat-producing elements — to the Moon’s nearside. That concentration of elements would have contributed to the volcanism that created the nearside volcanic plains.
The Moon’s nearside (left) is dominated by vast volcanic deposits, while the far side (right) has far fewer). Why the two sides are so different is an enduring lunar mystery. Credit: Brown University
A new study reveals that an ancient collision on the Moon’s south pole changed patterns of convection in the lunar mantle, concentrating a suite of heat-producing elements on the nearside. Those elements played a role in creating the vast lunar mare visible from Earth. Credit: Matt Jones
The nearside is home to a compositional anomaly known as the Procellarum KREEP terrane (PKT) — a concentration of potassium (K), rare earth elements (REE), phosphorus (P), along with heat-producing elements like thorium. KREEP seems to be concentrated in and around Oceanus Procellarum, the largest of the nearside volcanic plains, but is sparse elsewhere on the Moon.
KREEP material would have ridden the wave of heat emanating from the SPA impact zone like a surfer. As the heat plume spread beneath the Moon’s crust, that material was eventually delivered en masse to the nearside. The team ran simulations for a number of different impact scenarios, from dead-on hit to a glancing blow. While each produced differing heat patterns and mobilized KREEP to varying degrees, all created KREEP concentrations on the nearside, consistent with the PKT anomaly.
(Excerpt) Read more at scitechdaily.com ...
ping
HaHaHaHa............
Made of cheese, right?
A simpler explanation would be that
the far side of the moon is exposed to deep space
and whatever may be hurled at it,
while the near side of the moon is shielded from all of that by the earth.
That does make sense. Certainly when looking at the surface. I guess the “twist” here is the researchers are trying to explain the unequal distribution of materials in the mantle. Or something.
I mean funny like a clown?
I amuse you?
I make you laugh?”
Thanks BenLurkin. I guess the real question is, who's gonna bring up the obvious connection to racism. [ducks, runs]
Welcome to my world, btw. ;^)
That’s not a simpler explanation, because it’s not an explanation at all. Any part of the surface of the Moon, the Earth, the Sun, any body, is just as exposed as any other, apart from the tiny fraction that would hit the Earth instead of hitting the Moon if everything was lined up just right.
** ping **
Kamala snaps: “Who you callin’ a Two Faced Moon?”
Nope, the Earth doesn't provide significant shielding for the Moon. It's 8,000 miles in diameter, certainly bigger than the Moon, but it's 300,000 miles distant, meaning it provides a pretty much negligible barrier to space rocks. Visualize 8 vs. 300 -- it's like an 8-inch pie plate at a distance of 25 feet.
Regards,
I learned 240,000 miles in grade school (in the 1950s) and I do not believe it has changed since them.
But I do agree with you on the "insignificant shielding" issue.
If the moon split off from the earth way back when:
The near side was once part of the inside of earth, thus the vulcanism.
The far side the outside of the earth, but without the benefit of weathering to hide the meteoric scarring or plate tectonics to create mountains, etc.
Just expounding on a theory.
If the Moon is tidally locked to the Earth wouldn’t that mean that the Moon is more likely to be bombarded on the side facing away from us? Isn’t the Earth in the way of many asteroids and comets that would otherwise hit it on the side facing us?
I’d expect asteroids to either impact Earth or be gravity-whipped into space or impacting the moon. (There are many impacts visible on the near side—some of the earliest having been subsumed by molten rock).
The current theory is that the primordial Earth was struck by a Mars-sized planet, creating a debris field that became the Moon. Pretty much all of the materials would have been liquified, and even solid debris would have been absorbed by the coalescing bodies.
The Moon is far enough away that it does not receive much in the way of shielding from Earth. Even if you assume that the majority of objects that strike either are in the ecliptic, that’s still only about 2 degrees of coverage out of 360 - less than 1%.
However, when the Moon was formed it was much, much closer. Close enough for any number of effects, including the shielding that doesn’t happen now, as well as tidal stresses, mass transfers, etc. So the Earth could easily have been siphoning out the guts of the Moon at that time, resulting in the lava plains being created and sustained over the first couple of billions of years, and erasing the meteor craters that might have been created during that time. Over time the Moon has receded from the Earth and all of the effects I listed have moderated.
Procellarum KREEP terrane (PKT) — a concentration of potassium (K), rare earth elements (REE), phosphorus (P), along with heat-producing elements like thorium.
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Well now we know what all those alien mining operations are going after.
I'm old enough to remember my father telling me that no one knew what the far side of the moon looked like. When the Soviets managed to photograph the far side, my mother's immediate reaction was to doubt them, to think they were faking the photos.
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