Birth of the Moon: a Runaway Nuclear Reaction?

An anonymous reader writes "How the Moon arose has long stumped scientists. Now Dutch geophysicists argue that it was created not by a massive collision 4.5 billion years ago, but by a runaway nuclear reaction deep inside the young Earth."

Comments

It's a long but interesting article

[mcgrew]

I'm on page three. I had to look up a couple of things of wikipedia so far. I hadn't heard the word Petrology before; it's the study of rocks.

The term "georeactor" seemed self-explanatory but I looked it up anyway, and was glad I did.

Natural nuclear reactors
In the 1970s, geochemists documented the existence of naturally-occurring slow fission reactors in uranium-bearing geologic formations at Oklo in Gabon, Africa. The Oklo natural nuclear fission reactors operated approximately 1.5 to 2.0 billion years ago, when the natural occurrence of the uranium-235 isotope (required for the fission chain-reaction) was much higher.

[edit] Planetary fission reactors
Large, gaseous planets, such as Jupiter or Saturn, radiate more energy into space than they receive from the Sun. (In the case of Jupiter, the radiated energy is almost twice the received energy.) The source of this energy was originally attributed to gravitational contraction, since gravitational potential energy conversion into heat seemed to be the heat source of sufficient magnitude to account for the quantity of energy released. In 1992, J. Marvin Herndon postulated that the excess energy could be explained by the existence of a central nuclear reactor. High-density fissile elements (i.e. uranium) would be concentrated at the core and could undergo sustained nuclear fission chain reactions. Herndon demonstrated the feasibility of a planetocentric nuclear reactor using Fermi's nuclear reactor theory, calculations similar to those used in nuclear-reactor design.

[edit] The georeactor
Herndon subsequently realized that the calculations also permitted the existence of a similar reactor at the Earth's core. Herndon's calculations depend on certain unconventional assumptions regarding the composition of the core, in particular the oxidation state of uranium and the likelihood of its precipitating to the center. He justifies these assumptions by comparison with the composition of enstatite chondrite meteorites, which do have the necessary highly reduced oxidation states and are the only chondrite meteorites which have sufficient iron metal-alloy to match the composition of the Earth with its massive core.

Herndon argues that the georeactor is the energy source for the Earth's magnetic field, and that variations in the strength and direction of the field can be explained by natural variations in the operation of the georeactor.

[edit] Generalization to planetary magnetic fields
Currently active internally generated magnetic fields have been detected in six planets (Mercury, Earth, Jupiter, Saturn, Uranus, and Neptune) and in one satellite (Jupiter's moon Ganymede). Magnetized surface areas of Mars and the Moon indicate the former existence of internally generated magnetic fields in those bodies.

As Mr. Spock would say, "fascinating." My thanks to the story submitter.

Re:Wouldn't there be an empty space?

[moteyalpha]

There is a remnant of a naturally occurring reactor that operated in southern Africa 2 billion years ago so I suppose it is possible, however many other odd things are also possible. http://apod.nasa.gov/apod/ap021016.html

Re:Impactors all the way

[Maury Markowitz]

> it would have had to be between Venus' and Mars' orbits.

They quote this as a problem?!

The baseline assumption is that the impactor formed in the Earth's trojans, which fixes this "complaint" perfectly. Unlike Jupiter (for instance), the Earth's trojans are not entirely stable, and any large objects placed in it will drift back and forth. This explains a VERY large number of data points:

1) it explains geological makeup perfectly
2) it explains why the impact angle was grazing
3) it explains why the Moon formed so long after the Earth

See: http://en.wikipedia.org/wiki/Giant_impact_hypothesis

Maury

Re:Wouldn't there be an empty space?

[afidel]

Correct, the total volume of the oceans is ~1.3*10^6 km^3, the volume of the moon is ~2.2*10^10 km^3 so it's not even close.

Re:Teach the hypothetical controversy!

[db32]

Just to be fair to everyone here, there will be a variety of Christian-minded skepticism. To lump them all into one bunch is pretty dishonest.

We have group #1 that is going to claim the literalist nonsense. These are the folks that built the creationist fantasy tourist trap where children frolick with dinos in the displays.

We have group #2 that is probably going to take the approach you mentioned to various degrees. Some may say it could have been spontaneously created, but that is no reason to not investigate, we don't have a lot of good information yet. The other end will lean towards the idea that we haven't found any information yet and thus it must be spontaneously created. This is the realm of curable ignorance on one side and pseudoscience nonsense on the other.

Then we will have the final group, that thankfully has gained at least some traction. The group that will say "Sure God created it...and a runaway nuclear reaction or massive impact are two possible methods that the universe played out that caused it to be created...let's go figure it out." Despite the common slashdot groupthink on this subject, there are indeed quite a few very intelligent people that also hold religious beliefs and don't let those religious beliefs muddy up the science. Francis Collins and Ken Miller are two examples that jump to mind. (In fact, if you haven't seen Ken Miller's video on the ID/Dover trial business, it's about 2hrs, but it is an amazing lecture.)

Re:Wouldn't there be an empty space?

[adrianwn]

Dude, the European definition of billion is a thousand million, just like in the USA.

Huh? Where?! In German, French, Spanish and Italian, the word "billion" (resp. the words similiar to it) always means 10e12.

Re:Wouldn't there be an empty space?

[d3ac0n]

Keep in mind too, that the continental crust material is made up of significantly YOUNGER and lighter rock than the deeper crust. Most of the continents are made of (comparatively) light granite, limestone, sandstone, shale and loose aggregates of all stones. However, the lower crust and the deep ocean crust are made primarily from heavy Basalt.

So the idea that continents formed in the way they did due to the ejection of moon material is incorrect. Not only was the earth likely still a molten ball at that point, but the continents are made from material that did not even exist on earth until well AFTER the earth had solidified.

Re:How Big the Earth, How Thin the Crust

[Pearson]

The example I remember from school is that if the earth were an apple, the crust would be as thin as the skin of the apple. And we've never been able to drill all the way through even that "thin" skin.