Molten Core Inside The Moon?

beggs writes: "The Times (free reg et al.) is running an article about the possibility of a molten core inside the moon and that this, if confirmed may lend support the the theory that the moon is the child of a violent collision between mother earth and some other heavenly body in the distance past."

Comments

Even if it does have a molten core

[ObviousGuy]

The plate tectonics that would have ensued from having an active core (like Earth's) has ceased, for quite a long time too.

Re:Silly scientists..

[zulux]

It was proved (through observation) many years ago that the moon is made of cheese.

Now we know that it also has a rich-'n-creamy center! Mmmmmm... I'm hopping it's nougat, topped with caramel.

Energy

[dingo]

IF we had a moon colony how would a molten core compare to solar cells as an energy source?

Might be worth looking at.

Re:Energy

[doooras]

A molten core would allow for continuous Geothermal energy (methinks) which would be more useful than solar, since any given location on the moon is only facing the sun for half of each month.

BTW... love the sig.

Re:Energy

[Debillitatus]

...continuous Geothermal energy...

Yeah, this would be the Holy Grail of power sources for a moon colony. There would be a lot of energy down there, much more than we could use.

The only problem I could see is the same one which stops us from using geothermal effectively here; we can't drill deep enough to get a large enough temperature differential to make it worthwhile. Perhaps some engineer could elaborate on this...

Re:Energy

[Christopher Thomas]

IF we had a moon colony how would a molten core compare to solar cells as an energy source?

Solar would be better.

Especially with no atmosphere or weather to degrade the incoming sunlight, solar cells work quite well.

Geothermal is a pain to work with under the best of circumstances (you can only build a large-scale plant (no small power sources)), and even if the moon has an energy-producing core (tidally kneaded or (like Earth's) radioisotope-powered), the amount of energy flowing out of it is small compared to Earth's (no volcanism or rapidly convecting mantle). This means that the yield from geothermal on the moon will under the best of conditions be much lower than on Earth.

Given that solar power is so convenient, I don't see any strong reason to use geothermal. Power storage for half a month isn't *that* hard, and if you need enough power to make storage impractical, you can put big mylar mirrors in orbit around the moon to reflect enough sunlight to supply your photocells (probably cheaper than a power cable around the equator).

Re:Energy

[CheshireCatCO]

If you want to use geothermal energy, you need active geologic activity at the surface. The Moon doesn't have that, based on the many, many observations we've made of the surface. If there is a molten core at all, it's a tiny fraction of the volume, deep in the interior.

Geothermal maybe?

[CtrlPhreak]

Could this possibly lead to a cheap method of power generation on the moon in the future?

Its not The Times

[isorox]

The Times is a great paper thats been arround longer then america, this article is from the New York Times

No way

[AllMightyPaul]

Having a molten core would NOT lend support to the theory that the moon splintered off of the Earth. In fact, the non-existence of a molten-core would better lend support to that theory than a molten core. This is simply because if the moon splintered off of the earth, it is going to be one giant rock. How does one get a molten core from just a rock? Does anyone else see what I'm saying?

Re:No way

[Transcendent]

What a lot of people are missing is the fact that the moon is in such an orbit that only one side faces us at any given time (look for yourself.... heh). This orbit is far to delicate for any captured rock, or huge chunk of earth that was smashed off by an asteroid could create, it had to have been that the moon was an actual part of the earth, but gave the earth a lop-sided form. So centripital (spelling?) force caused that chunk to rip off from the earth, creating the moon we have today.

(no, it doesn't have to be necessarily a chunk, but most likely a big scoop pf molten rock... from when the earth was in a molten state.)

Did you really think we thought a large object hit Earth, and ejected a perfectly spherical rock?

Well thats how everything started. Basically huge chunks of rock slammed together to make the planets, and over time, smaller ones filled in the gaps, the pressure created a molten core, and the core smoothed everything out.

Re:No way

[CheshireCatCO]

Darwin's (no, George Darwin, Charles's son) idea about planetary fission to form the Moon doesn't work. There's insufficent angular momentum in the system to make it work. The giant impact model is the ONLY model that makes sense right now. (The tidal locking of the Moon causing it to show us one face at all times has nothing to do with anything.)

In fact, the original poster is correct: if the Moon formed in a giant impact, it appears that it should be almost all rock akin to Earth's mantle. The iron and other metallic elements would have sunk into the interior of the Earth, being lost to the disk of debris what would go on to form the Moon.

Re:No way

[shrikel]

most likely a big scoop pf molten rock... from when the earth was in a molten state

The earth IS in a molten state as we speak! There's a little crust on the outside, but, proportionally speaking, it's many many times thinner than the shell of an egg. The earth could be hit by a large celestial object TODAY, (even a 200-mile wide blob of frozen ammonium, which is VERY cold) and tomorrow you wouldn't be able to tell that the earth had EVER had a crust. It's not that the force of the impact would melt the entire crust, it's just that it would break the shell and let all the hot insides come out and melt the crust.

Re:No way

[drudd]

What a lot of people are missing is the fact that the moon is in such an orbit that only one side faces us at any given time

Yes, this is true... it also has nothing to do with how the moon formed. Angular momentum transfer from tidal forces automatically forces an orbiting body into just such a configuration. It's called being tidally locked. This same process has caused the earth's rotation to slow, and to increase the average radius of the moon's orbit.

Doug

Aren't there easier tests?

[looseBits]

Measuring fluctuations in the Moon's size obviously tell you if it is solid or not but what about looking at the magnetic field. If the core of the Moon is liqued, then you wouldn't you see a large magnetic field from the free flowing ions in the core? That is what is responsible for the Earth's field.

Re:Aren't there easier tests?

[CheshireCatCO]

The Moon appears to once have had a magnetic field, but if our theories of field generation are right, it's rotating too slowly now to have any real field.

Re:Aren't there easier tests?

[CheshireCatCO]

Yes, exactly. This rotation is thought to be too slow to support a strong field, particularly in a body with such a small, if any, core.

Re:Silly scientists..

[birder]

Unfortunately, it's one of those stinky French cheeses.

Good with fondue.