Moon question.

[SmokeyJoe]

Just read that the crust on one side of the moon is thicker that the other (can't remember which way round). Does anyone know why?

Sent from my A500 using Tapatalk 2

[RoloFanatic]

If i remember correctly, the crust on the far side of the moon is thicker. I dont know exactly why other than it has something to do with the effect of earths gravity on the moon.

[JamesF]

Wikipedia suggests that the crust on the far side averages 12km thicker than the near side, but doesn't suggest why. Perhaps it is related to the fact that the maria have formed on the face nearest to us and not on the far side?

James

[sonic190178]

maybe it has to do with the massaive impact on the far side

[zakkhogan]

the way i understand it is.....

The moon has always been tidally locked, however one theory is that it hasnt always been locked faceside towards Earth. Some believe that the farside was facing earth during its formation.

This theory would then have us believe that the moon was struck by a massive meteor causing it to spin on its axis and eventually lead to it being tidally lock the way it is now.

My assumption would be that the side facing earth during formation would be under greater gravitational stress causing the thicker crust.

I'll see if i can find something to back this up....

[zakkhogan]

here is a little bit about what i was talking about, but it dosnt really say much about anything.....

http://www.dailymail.co.uk/sciencetech/article-1126543/Far-moon-faced-Earth-asteroid-flipped-around.html

[kenmyers]

Their is growing evidence that the far side of the moon was struck by a large body at slow velocity and this body conglomorated on to the far side. In effect it melted onto our moon. It is still a theory but not just the thickness is supprising but also the composition of the rock is different to our side giving more weight to this theory.

[kenmyers]

Wikipedia suggests that the crust on the far side averages 12km thicker than the near side, but doesn't suggest why. Perhaps it is related to the fact that the maria have formed on the face nearest to us and not on the far side?

James

Also lending to the above theory is that the far side has NO maria at all. NONE. very odd.

[SionR25]

Found this picture on wikipedia showing the distribution of maria across the whole lunar surface. Not much at all on the far side.

[RoloFanatic]

Also lending to the above theory is that the far side has NO maria at all. NONE. very odd.

This is incorrect, there are far fewer marae on the far side of the moon but there are some marae there

[SmokeyJoe]

Thanks guys, the amount of knowledge human kind has gained in my life time astounds me , but I am equally astonished by just how much we don't know. The moon freaks me out a little just sitting there in exactly the right place to give us loads of clues about the nature of the universe. I'm not saying I am convinced about ets but if I had major planet building abilities that's the kind of thing I'd do.'

Sent from my A500 using Tapatalk

[kenmyers]

I am a intrested to say the least on how little marae is on the far side. The answer is surely mind boggling. Mars is the same, north is devoid of features yet the south has everything! how odd indeed!

[SionR25]

Couldn't you really say the same about earth as it is now. Hardly any land in the southern hemisphere, most of i concentrated in the north, or even either side of the pacific.

Sion

[seigfriedwilson]

Yes, but that is more to do with plate tectonics then anything else. Given enough time, the land will be back to one enormous Gondeland again, possibly in the Southern Hemisphere.

The moon was volcanic at one stage, hence the marias, which could be one suggestion?

Also , isn't the far side more heavily impact crateted? Could that not have erased details?

It's an interesting discussion. Good question.

Seigfried

[SionR25]

Do we know that features on other large bodies and planets won't move with time though?

Sion

[seigfriedwilson]

Pretty much, as they lack the molten core to drive 'continental drift'.

Seigfried

[SionR25]

Ok, thanks .

Sion

[JamesF]

I have no scientific evidence for this, but it has struck me that once the Moon and Earth were locked together so the Moon always faced the Earth the same way, the Earth might help to shield that side from impacts thus preserving the maria to some extent, whereas the "outward" side had no such protection and might therefore have any maria rendered unrecognisable. Equally, I can think of all sorts of reasons that might not work

James

[seigfriedwilson]

That what I was thinking James. More research required I think.

Seigfried

[Naemeth]

I have no scientific evidence for this, but it has struck me that once the Moon and Earth were locked together so the Moon always faced the Earth the same way, the Earth might help to shield that side from impacts thus preserving the maria to some extent, whereas the "outward" side had no such protection and might therefore have any maria rendered unrecognisable. Equally, I can think of all sorts of reasons that might not work

James

Especially plausible if the Moon was struck early on in it's formation, but after it cooled down to a certain extent, because had it still be hot, it's likely that the entire surface would become molten by the impact and thus be roughly the same all the way around.

However, it has been said on "The Planets" (BBC Documentary) that the Moon's surface is pretty much all the same age, how could this be if the impact was after the Moon had cooled somewhat? Mind you, this is a 12 year old documentary, what we know now has progressed since then.

I suspect the surfaces of Jupiter, Saturn and Neptune to be geologically as stable as the Earth, and thus probably change over millions of years (if they have surfaces in the sense we see them), because they are massive enough to have retained heat in their cores.

[Ronnie67]

it could be a number of factors which caused one side of the moon to be thicker than the other, The Earth is very close to the Moon, and its gravity is stronger on the near side of the moon than on its far side, bombardment of metors on the far side, including larva flow

[stuffedhaggis]

Thanks guys, the amount of knowledge human kind has gained in my life time astounds me , but I am equally astonished by just how much we don't know. The moon freaks me out a little just sitting there in exactly the right place to give us loads of clues about the nature of the universe. I'm not saying I am convinced about ets but if I had major planet building abilities that's the kind of thing I'd do.'

Sent from my A500 using Tapatalk

i am in the same opioan as this

[sologuitarist61]

As the moon and Earth of tidally locked then you would think that the opposite might be true and that the thicker crust would be on the side facing the Earth. Also, the side facing the Earth seems to show more evidence for big impacts/melting surfaces (the maria) than does the far side. Clearly a place of constrictions, especially now that the thinking is that the moon is made up more of earth substances than of the planetesimal that supposedly struck the Earth to form the moon in the first place.

[SmokeyJoe]

Just a general point, it seems to me that the more planetary systems we find outside of our own, the more our current theory of solar system evolution seems to be soon shaky ground.

Sent from my A500 using Tapatalk 2

[Ronnie67]

We always see on side of the Moon because it is gravitationally locked, therefore the near side feels more gravity than the far side, resulting in a uneven crust thickness.