Did the Moon Form from a Nuclear Explosion?

This idea about the possibility of the moon forming in a nuclear explosion is at least three years old, but it still doesn't appear in Wikipedia which lists several different ideas about how the moon may have formed. However the final paper describing this idea was only published about half a year ago.

Let's start by examining some of the Wikipedia comments about the moon:

The prevailing hypothesis today is that the Earth–Moon system formed as a result of a giant impact, where a Mars-sized body (named Theia) collided with the newly formed proto-Earth, blasting material into orbit around it, which accreted to form the Moon.

However, this prevailing idea has some problems:

Despite its accuracy in explaining many lines of evidence, there are still some difficulties that are not fully explained by the giant impact hypothesis, most of them involving the Moon's composition.

In 2001, a team at the Carnegie Institute of Washington reported the most precise measurement of the isotopic signatures of lunar rocks.[27] To their surprise, the team found that the rocks from the Apollo program carried an isotopic signature that was identical with rocks from Earth, and were different from almost all other bodies in the Solar System. Since most of the material that went into orbit to form the Moon was thought to come from Theia, this observation was unexpected. In 2007, researchers from the California Institute of Technology announced that there was less than a 1% chance that Theia and Earth had identical isotopic signatures.

Is it a logical inference from those statements that we could conclude there is less than a 1% chance the prevailing hypothesis is correct? The composition of the moon doesn't seem to match the prevailing giant impactor theory.

There is an alternate hypothesis that Wikipedia doesn't even mention in their list of hypotheses currently:

Did the Moon Form in Natural Nuclear Explosion?

there’s another theory called the fission hypothesis that could account for the similar isotopic content. This idea is that the Earth and Moon both formed from a rapidly spinning blob of molten rock. This blob was spinning so rapidly that the force of gravity only just overcame the centrifugal forces at work.

In this system, any slight kick would have ejected a small blob of molten rock into orbit. This blob eventually formed the Moon.

The fission hypothesis has been studied for 150 years but ultimately rejected because nobody has been able to work out where the energy could have come from to kick a lunar-sized blob into orbit.

Nobody worked it out until about 2010, when the possibility of a nuclear explosion was suggested:

Their idea is that centrifugal forces would have concentrated heavier elements such as uranium and thorium near the Earth’s surface on the equatorial plane. High concentrations of these radioactive elements can lead to nuclear chain reactions which can become supercritical if the concentrations are high enough.

So if a natural nuclear explosion kicked enough mass off the Earth to form the moon, wouldn't it leave a radioactive signature on the moon? Yes it would, and looking for that signature is how the theory can be tested:

They also say that there ought to be telltale evidence that such an explosion took place, particularly in the lunar abundance of helium-3 and xenon -136, which would both have been produced in great quantities in a natural georeactor.

The problem with that is, there's lots of helium-3 on the moon's surface from the solar wind, so sorting that out from the helium-3 from a nuclear explosion would be a challenge. To prove this idea, we would need to look for helium-3 below the surface where it didn't come from solar wind.

So someday we might be bale to collect better data to confirm, or perhaps reject this theory. But until then, don't you find it interesting that it might solve the biggest problem with the giant impactor theory? (The problem being that the moon's composition is too much like the Earth and it's unlikely the impactor's composition would match that of Earth so well).

After reading about this hypothesis, I'm unsure why the giant impactor idea is still the prevailing hypothesis, since the nuclear explosion idea seems to have a better fit with the composition of the moon.

What does ATS think about this idea about a nuclear explosion forming the moon? Does it seem like it explains the moons composition better than the prevailing theory about the giant impactor?

Other articles:
Moon May Have Formed in Natural Nuclear Explosion
The Moon may have formed in a nuclear explosion

If you prefer more technical information, here's a link to the paper on arXiv:
An Alternative Hypothesis For The Origin Of The Moon

reply to post by Arbitrageur


Cool thread
I've never liked the impactor theory but was not aware of the nuclear explosion alternative , I will have to check out your links but on the face of it it sounds like a plausible alternative .
If this theory is correct would this not imply that most planets will have moons created through the same processes ?

Excellent thread!
When I first saw the title, I feared this would be about some ancient aliens theory of how a former civilization destroyed their world in a nuclear holocaust, and subsequently created the moon in the process.

I have never heard of a natural nuclear explosion before. Will have to look it up before I can comment any further. But if you can share some information of what might create such an reaction, it would be appreciated.

I'm guess that if the nuclear explosion theory is true, this would have had to be an explosion of extraordinary magnitudes, to actually create the moon. I also imagine that it would have taken place internally, and therefore would have been created internally in the planet. I honestly think it sounds a bit too amazing, but this is not an area I know anything about, so if you can share anymore information, I would love to hear it. Are there processes inside our earth that create nuclear explosion?

- could the kind of nuclear explosion that you are referring to happen again then?

Originally posted by gortex
If this theory is correct would this not imply that most planets will have moons created through the same processes ?

Good question. I'm not sure but I don't think gas giants are candidates, and here's why.

Since it's a nuclear fission reaction which has been proposed, that requires heavy elements and relatively high density. Also my understanding is this concentration needs to occur toward the surface, as the proto-planet spins rapidly. So I suspect only rocky planets with relatively high densities would be candidates, and not gas giants.

Jupiter might have fissionable materials, but even if they went critical and exploded relatively close to the core, it might not eject a moon because the explosion wasn't close enough to a dense surface. But if we find the composition of a moon closely matches the composition of a planet as is the case with our moon and Earth, that would suggest exploring the possibility even if it's a gas giant.

Originally posted by Mads1987
Are there processes inside our earth that create nuclear explosion?

As you know we have man-made nuclear reactors, and as seen in Chernobyl they have gone critical. We do know that there have been natural nuclear reactors:

lunarscience.nasa.gov...

Of course, georeactors are by no means hypothetical. The most famous is in Oklo in Gabon, not so far from the equator, where a natural nuclear reactor was clearly in operation until about 1.5 billion years ago, leaving telltale signs in the uranium deposits now being mined.

However I'm not aware of evidence showing that or any other natural reactor exploded, but it's not a huge leap from a reactor to a reactor explosion in my view.

- could the kind of nuclear explosion that you are referring to happen again then?

I doubt it. The half-lives of fissionable materials are a measurement of their decay, and as they decay they become less likely to start a chain reaction or become critical. My guess is anything that was going to explode in the Earth from nuclear fission has probably already exploded, if such an event ever happened.

I think it is kind of impossible to know for sure how the moon was formed. I guess it doesn't hurt to speculate on the creation of the moon though, as long as in a hundred years the moon's creation ideas aren't shoved down our populations throats as facts.

reply to post by rickymouse


Meijer, Anisichkin, and van Westrenen have suggested a way to test the idea, for example by looking for helium-3 below the surface of the moon (or other traces of a nuclear explosion). So the hypotheses is presumably testable, but right now we don't have any convenient way to go digging below the surface of the moon for samples to test the idea. If we did find evidence of a nuclear explosion, then I don't see why it would be that speculative, and if we didn't, we could rule out that idea and look for another hypothesis that explains what the giant impactor theory doesn't.

reply to post by Arbitrageur


Thanks for the insight. I am surprised to learn about the natural nuclear reactors. Didn't know that kinda stuff happened on/in planets.

Not sure if I'm ready to jump on the bandwagon, but it sounds like a plausible theory. Wasn't aware of how much the evidence conflicted with the current impact theory. Real interesting stuff.

reply to post by rickymouse


Why do you think it is 'kind of impossible'?
And whats with the 'shoved down our populations throat as facts'-statement?

Each and every day people present the most outrageous things as being factual, things that may actually change how we live our lives... and you are concerned that someone might try to convince you that the moon was formed through a nuclear explosion? I mean.. either they have the evidence for it, or they don't... science doesn't shove, it presents.

Has there ever been a natural nuclear explosion? Is such thing even possible? Chernobyl didn't explode like a nuclear bomb, it was a steam explosion, allegedly followed by a hydrogen + oxygen explosion. You can't achieve a chain reaction by just having lots of radioactive material together.

As for the giant impact hypothesis, it isn't in danger zone because of the Moon's composition. It's quite possible that Theia was a high-density iron-nikel proto-planet core, which blew the material off earth's crust and then sank in to join the earth's core. The blown-off material from the crust then formed the Moon. When I read that the Moon's composition is basically the same as the composition of the earth's crust, that's the first thing that came to my mind.

To their surprise, the team found that the rocks from the Apollo program carried an isotopic signature that was identical with rocks from Earth

Maybe the reason for this anomaly is because the rocks they claim are from the moon, are actually from the Earth.

As to the theory concerning a nuclear occurrence was the reason why the moon was formed...wasn't the Universe created by a "BIG BANG"? It seems that it is likely that some kind of nuclear fission/fusion reaction that created all the surrounding celestial bodies would be the same reason the moon was formed, but really....does it matter how...and could anything every be proved?

reply to post by Arbitrageur

... the team found that the rocks from the Apollo program carried an isotopic signature that was identical with rocks from Earth, and were different from almost all other bodies in the Solar System.

This is a very curious statement considering that we have only seen return samples from one asteroid (Hayabusa) and our moon to begin with. Besides that, we do have meteorites that we suspect are from Mars which we rely on... unless they show possible signs of past life, in which case the evidence is quickly disavowed.

All in all, to say that the moon is identical to Earth while different from the most of rest of the solar system that we haven't even yet begun to explore in earnest, seems to be more a leap of faith than anything else.

Originally posted by wildespace
Has there ever been a natural nuclear explosion? Is such thing even possible? Chernobyl didn't explode like a nuclear bomb, it was a steam explosion, allegedly followed by a hydrogen + oxygen explosion. You can't achieve a chain reaction by just having lots of radioactive material together.

If the moon is evidence for a nuclear explosion, then the helium-3 under the surface and other signatures would be the supporting evidence. But even without that the composition of the moon seems to align better with the theory that doesn't involve the giant impactor. As I said we have evidence of a natural nuclear reactor. The authors of the paper suggest a couple possibilities for how nuclear material might become concentrated enough to explode. The bomb over Hiroshima was certainly evidence of an explosion from nuclear fission.

As for the giant impact hypothesis, it isn't in danger zone because of the Moon's composition. It's quite possible that Theia was a high-density iron-nikel proto-planet core, which blew the material off earth's crust and then sank in to join the earth's core. The blown-off material from the crust then formed the Moon. When I read that the Moon's composition is basically the same as the composition of the earth's crust, that's the first thing that came to my mind.

Has anyone modeled that? From what I've read models showed the moon would have 80% of its composition from Theia and 20% from Earth, so if this is true, the density of the moon is too low for what you suggest.

An Alternative Hypothesis For The Origin Of The Moon

Regardless of the collision parameters, all successful simulations indicate that by mass approximately 80% of the Moon would originate from the impactor, with only 20% originating in the Earth (e.g. Canup, 2008).

If this is true the density of the moon would be higher if the impactor had a dense iron-nickel composition. But if you have other models showing something else this would be a good place to share them.

The authors of the paper imply that even if this nuclear explosion hypothesis is incorrect, they think the giant impactor theory has large problems with the moon's composition so some other hypothesis is probably needed:

Our main aim is not to convince readers of the validity of our alternative hypothesis (although that would be nice); our goal is to convince readers that
(a) the classic giant impact model is facing serious problems in light of a growing body of increasingly sophisticated chemical analyses and dynamical simulations and
(b) alternative models should be developed and tested.

Originally posted by redoubt
This is a very curious statement considering that we have only seen return samples from one asteroid (Hayabusa) and our moon to begin with. Besides that, we do have meteorites that we suspect are from Mars which we rely on...

Don't forget the huge collection of over 30,000 meteorites we have amassed, not just those thought to be from Mars.

Originally posted by soulpowertothendegree
and could anything every be proved

Scientists say that evidence supports a theory. In order for a theory to be scientific it must be falsifiable which means nothing is ever proven.

We do know how to look for evidence of this hypothesis. Now it's just a question of whether we will do that or not.

I heard this theory before, and a few questions came to mind which made it implausible at least for me;

Why did only Planet earth have this occurrence,

What could drive the planet to spin so fast

How does this explain the Ringing "vibrational" effect of impacts on the moon (That it may be hollow)

How does this explain how we have a Perfect Eclipse and no where else in the known universe (Ratio between distance of the moon and her size is perfect, this is mathematically highly implausible)



However i must say, i agree that this theory is much better than Theia impact theory,

I would do more than just poke holes in the theory, however back when i researched the Moon, I ended up with more questions than answers, and have no alternate theory or useful data to add . The Moon is sure a tricky one, and im sure she will hold on to her secrets for quite some time.

Great thread S & F
Namaste

reply to post by Arbitrageur

Don't forget the huge collection of over 30,000 meteorites we have amassed, not just those thought to be from Mars.

Oh, no doubt... but their origins?

When we landed the Viking missions on Mars, we sampled the atmosphere and found a match with some of those meteorites. But... we haven't landed on Mercury or any of moons of Jupiter or Saturn's or Neptune or Uranus. Science from Soviet missions to Venus is scrubby at best.

None of this is to say that 'evidence' does not exist to link various rocks with various, as yet un-visited locations. But we still have to go it to know it...

Our moon is one of the most mysterious, enigmatic bodies in our solar system. I just wish we spent more time landing there and less time crashing things into it, lol.

There are some mathematical anomalies that would make this theory very difficult. Now I am just speaking from things I seemed to have heard....something about the size of the moon and the distance of the Earth from the Sun and the ratio of the moon something about 400...seems more likely that the moon is part of the Fibonnaci cycle and that it has to be where it is mathematically, it could be a artificial satellite placed there as a listening device by the NSA , who knows....

Originally posted by WiseThinker
I heard this theory before, and a few questions came to mind which made it impossible at least for me;

Why did only Planet earth have this occurrence,

What could drive the planet to spin so fast

In a word, chaos. Solar system formation is believed to be a chaotic process.

How does this explain the Ringing "vibrational" effect of impacts on the moon (That it may be hollow)

The moon isn't hollow and this is unrelated...it could still "ring" if the isotopes matched Theia instead of Earth.

How does this explain how we have a Perfect Eclipse and no where else in the known universe (Ratio between distance of the moon and her size is perfect, this should be mathematically highly implausible)

I would say that not only is it plausible, it's inevitable that the size would match at some point, as a consequence of the moon's orbit increasing.

It's not perfect, but it is close, and only temporarily. For most if the time the moon existed this was not the case, as the moon was closer to Earth. And it won't last much longer on astronomical time scales, since the moon is still moving away. So it's just your luck that you were born at the right time to see it. If you had been born as a dinosaur hundreds of millions of years ago, the size wouldn't be that close.

Great thread S & F

Thanks

reply to post by Arbitrageur


Venus might have acquired its slow retrograde spin as the result of a similar collision (plus tidal forces from the Sun). There was also a theory that Mars' moons were the result of a collision. So these things can happen in the Solar System.