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Moon Space

Birth of the Moon: a Runaway Nuclear Reaction? 355

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."
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Birth of the Moon: a Runaway Nuclear Reaction?

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  • by mnslinky ( 1105103 ) * on Thursday December 11, 2008 @09:33AM (#26074467) Homepage

    Wouldn't there be evidence of this on the surface somewhere? I know the crust has shifted considerably, but that's a *lot* of material to suddenly vacate.

    • by Fallen Kell ( 165468 ) on Thursday December 11, 2008 @09:37AM (#26074517)
      If it happened during the time that the earth was mostly molten, then no, there would be on evidence...
      • by WhiplashII ( 542766 ) on Thursday December 11, 2008 @10:41AM (#26075491) Homepage Journal

        I'm not sure I agree - The moon has an ungodly amount of angular momentum. I'm having trouble coming up with a method whereby a section of object a leaves object a, and then has enough thrust perpendicular to the direction of object a to get up to it's 1km/s orbital velocity.

        • by Smidge207 ( 1278042 ) on Thursday December 11, 2008 @10:56AM (#26075695) Journal

          People like you are what makes arseholes like Bevets cry at night and hold themselves...you with your "science" and "evidence." Bah! A pox on you!

          =Smidge=

        • Re: (Score:2, Interesting)

          by maxume ( 22995 )

          In a molten scenario, center of mass a would have ejected center of mass b, and then the countless fragments would have spent a bunch of time coalescing.

          It's been a long time since I have though about it, and I'm no expert, but I think that the Sun could have spent some time pulling on the moon, making the orbit both more in plane with the orbit of the Earth (the Earth is pulling too...), and faster, so not all of the momentum necessarily had to come from the explosion/ejection (tilting the plane of the orb

          • by WhiplashII ( 542766 ) on Thursday December 11, 2008 @12:45PM (#26077441) Homepage Journal

            The sun's gravity accelerates things near the Earth by 0.006 m/sec^2. Two objects close enough to be meaningfully gravitationally linked while orbiting the sun in the Earth's orbit will have a maximum differential acceleration of maybe a thousandth of that. So to get to 1000m/s takes 5 years.

            So this essentially posits that an explosion had enough force to blown the planet apart, and send the pieces into space, but not to escape velocity (11.2 km/s) but instead to a velocity just short of that (11.19 km/s or so), so that the moon goes flying away for 2.5 years but 2.5 years later comes back and settles into a nice, circular orbit.

            That would be hard to accomplish on purpose - saying an accident did it is beyond belief.

        • by 2names ( 531755 )
          How about the fact that the Earth was moving (around the Sun) when the ejecta started to be pulled back? I don't believe it would take much of a shift at the Moon's distance to allow it to "fall" into orbit, but, then again, IANAA.
        • Am I the only one that's just given up even bothering to read these new "how the moon was made" theories? It seems like there's a new one every year and none of them are really ever any better than the previous ones. Parent's points regarding the plausibility of this particular theory are a good example.
        • Re: (Score:3, Interesting)

          by adisakp ( 705706 )
          I'm assuming that if the moon was made from a fairly large amounts of ejected matter, that it would have formed from a gradual gravitational aquisition of the mass. Those other moons and planets that form this way have pretty large angular momentum.

          Also important to note, the moon is pretty much tidally locked (the same side always faces the earth). It's inconceivable that Earth's gravitational field did not play an extremely key role in the current angular momentum of the moon. For more information, r
    • by Gotung ( 571984 )
      The article is slashdotted but it is possible that when this happened there was no solid surface yet to leave traces of this.
      • by Dystopian Rebel ( 714995 ) * on Thursday December 11, 2008 @09:56AM (#26074813) Journal

        The article is slashdotted but it is possible that when this happened there was no solid surface yet to leave traces of this.

        No, I think the article was slashdotted today.

        The server in flames may leave traces on the floor and walls of the server room, but we'll have to wait for a "Best Way For Bright Child To Clean Server Room?" post to Ask Slashdot to confirm.

        • Re: (Score:3, Funny)

          by Thuktun ( 221615 )

          So when the server melted down from the Slashdot effect, was there a runaway reaction that caused a smaller, satellite server to be ejected?

    • Re: (Score:3, Interesting)

      by psyklopz ( 412711 )

      The pacific ocean is a big, empty space.

      • Re: (Score:3, Interesting)

        That's what George Darwin said, but no. There's not enough evacuated volume there. Think about it: the Pacific is huge, but not very deep on planetary scales. Volume-wise, you're off by orders of magnitude. (I don't believe Darwin knew the depth of the ocean, so he's off the hook.)

        • by afidel ( 530433 ) on Thursday December 11, 2008 @10:21AM (#26075173)
          Correct, the total volume of the oceans is ~1.3*10^6 km^3 [hypertextbook.com], the volume of the moon is ~2.2*10^10 km^3 [wikipedia.org] so it's not even close.
          • by afidel ( 530433 ) on Thursday December 11, 2008 @10:24AM (#26075217)
            Doh, make that ~1.3*10^9 for the oceans, stupid online references using the european definition of billion. Still makes it off by more than an order of magnitude.
            • Re: (Score:2, Insightful)

              by hobbit ( 5915 )

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

              You might be thinking of the UK, which used to call that a milliard, but even the UK has been with the program since the 1970s.

              • Re: (Score:2, Insightful)

                Europe counts more languages than one, and "milliard" or something similar to it means a "thousand million" in all but one, which itself is influenced by the US bastardisation of the term and is closer to being the 51st state than a part of Europe, really.

              • by adrianwn ( 1262452 ) on Thursday December 11, 2008 @10:49AM (#26075603)

                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.

              • I live in Europe (Netherlands) and last time I checked a milliard was still a 1000 million and a Billion is a thousand milliard. Perhaps the UK changed its definition, but the French/Dutch/German speaking nations haven't. No clue about the rest of Europe.
                • Re: (Score:3, Informative)

                  by Klaus_1250 ( 987230 )
                  Should have Googled for posting. Nearly all European countries use the Long Scale, some use the Short Scale but with milliard. In fact, the UK is the only European country to do it differently (why doesn't that surprise me, the bloody bastards still drive on the wrong side of the road too). See http://en.wikipedia.org/wiki/Long_and_short_scales [wikipedia.org]
                  • In fact, the UK is the only European country to do it differently (why doesn't that surprise me, the bloody bastards still drive on the wrong side of the road too).

                    Yeah, well that's why you were occupied by the Germans during WWII and we weren't. It's damn hard to steer a left-hand-drive tank on the wrong side of the road.

                    Although perhaps the 22 miles of water helped as well ;)

                    • Re: (Score:3, Informative)

                      by clone53421 ( 1310749 )

                      Yeah, well that's why you were occupied by the Germans during WWII and we weren't. It's damn hard to steer a left-hand-drive tank on the wrong side of the road.

                      You don't. You steer it wherever you please, and everyone else moves the hell out of your way. :p

          • by Kagura ( 843695 ) on Thursday December 11, 2008 @10:51AM (#26075617)

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

            Not to mention, according to the Giant Impact Hypothesis [wikipedia.org], the iron core of the mars-size body that struck the earth sunk down and was mostly absorbed into the earth's core. The moon has far less iron in its core than most other bodies in the solar system. Consider also that tectonic plates [wikipedia.org] have been moving for billions of years and have formed more than a dozen different "super-continents" [wikipedia.org] over time in various configurations. There's no way the Pacific ocean is a gouge from the moon-making.

    • by Goaway ( 82658 ) on Thursday December 11, 2008 @09:38AM (#26074545) Homepage

      Others mentioned the Earth being molten, but even as it is now, the Earth is plastic enough that if you removed a big enough chunk, the rest of the planet would flow and deform until it was spherical again.

      • Re: (Score:2, Interesting)

        by Hoi Polloi ( 522990 )

        I'd take anything in Cosmos magazine with a healthy dose of skepticism. Since the article is slashdotted these points may already be addressed but anyway...

        There is growing evidence based on analysis of ancient crust and zircon crystals that cratons (continental cores) formed much earlier than thought and that the earth was only molten for a very short period, if at all.

        I would say there should be evidence of a massive mineral anomaly in the earth's crust. No massive nuclear eruption big enough to put the

        • by Alien54 ( 180860 ) on Thursday December 11, 2008 @11:25AM (#26076155) Journal
          Just how much crust there is is often misunderstood.

          Example: imagine a model of the earth where 1 mm = 1 mile. (or you can use 1mm = 1 km, if you like)

          The earth is 7926.28 miles (12756.1 km) in diameter.

          At this scale, you can make out significant mountain ranges, etc. The Atmosphere would be 4 or 5 inches deep. The crust is an inch or 2 thick.

          And the Earth itself is more than 8 yards across. That inch or two of crust is sitting on a chewy molten insides. (check volcano flows, etc.)

          The Earth is really a molten droplet spinning in space with the thinnest external layer where life has happened to accumulate, like the layer of tarnish on a coin.
    • by moteyalpha ( 1228680 ) * on Thursday December 11, 2008 @09:52AM (#26074751) Homepage Journal
      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 [nasa.gov]
      • offtopic:

        Look at the old Astronomy Picture of the Day from 1995. Like this one for example: http://apod.nasa.gov/apod/ap950629.html [nasa.gov]

        The picture is in midget form... a tiny 36 kilobytes! They probably had to make it that small to "squeeze" through the slow 28k modems of the day. The web has really grown in size since then - today's average APOD is 200 kilobytes.

        • Plus in those days, a lot of the APODs were GIFs. 256 colors FTW! Also remember that 640x480 and 800x600 screen solutions were prevalent, so those tiny pictures were much bigger.

          I did some artwork on my Amiga using that infamous HAM-mode graphics editor whose name escapes me now. There was a video mode that allowed you to cover the "whole screen" as opposed to the normal boundaries, but it was still only 320x240 and change in size. Seeing those images on a PC in 800x600 mode some time later made me real

    • by CheshireCatCO ( 185193 ) on Thursday December 11, 2008 @10:06AM (#26074955) Homepage

      Everyone who has replied so far makes fair points, but misses the biggest point: the Moon is over 4 billion years old. There are virtually no rocks on the Earth's surface that even approach its age. That means that the ENTIRE Earth's surface has been replaced and reshaped in the interim. Things haven't just "shifted considerably", we've got a totally different surface. Any scar from that period is long, long since erased. And hole as deep as the Moon has long since filled in since the Earth is still very much a fluid over these timescales.

    • by aliquis ( 678370 )

      If the planet was that hard and cool back then how would you explain that the moon got round to? Obviously it wasn't that solid ..

      (or friction between pieces has grinded them down and melted them together with time but that sounds less likely I guess.)

    • It is called the pacific ocean.

      Even the traditional theories suggest that the pacific ocean is a scar created by the impact scraping off the continent and throwing it into orbit (yes I am simplifying).

      While this new theory has issues (angular momentum), if it is true, the Pacific Ocean basin is proably the ste it happened.

    • Of course there is the concept that the simplest solution is more likely. The concept of a huge collision from a large object on the earth seems more likely and possible then a Nuclear Reaction of such size.

  • the moon is made of cheese

    clearly, the young earth was lactose intolerant, and ejected it for that reason

    the problem is all infants can digest lactose, and lose the lactase enzyme ability later in life if they don't have the right genes

    but all theories have holes in them

    like swiss cheese!

  • by bytethese ( 1372715 ) on Thursday December 11, 2008 @09:37AM (#26074519)
    Check. Dutch Scientists, Check. Thought that the moon was caused by a Cosmic Dutch Oven, Priceless.
  • Sanitation (Score:5, Funny)

    by Anonymous Coward on Thursday December 11, 2008 @09:39AM (#26074551)

    So Earth basically got a bad case of gas, had an accident and now has its own turd in orbit.

  • by squoozer ( 730327 ) on Thursday December 11, 2008 @09:41AM (#26074579)

    While it's certainly an interesting idea I can't see it being right (but I've only read the first page, the site seems to have collapsed). My problem with it is simple that the impactor idea seems to fit all the data so well I think it's unlikley to be wrong.

    I wonder though if this could perhaps be tested. The huge explosion theory could well have left old rocks away from the explosion site untouched. The impactor would have melted the whole planet. If we find even one rock old than the impact date we have our answer.

    • by Canazza ( 1428553 ) on Thursday December 11, 2008 @09:54AM (#26074783)
      We may never *know* for certain. We can have hypothesis after hypothesis, and although the giant impact fits the data nicely, and is unlikely to be wrong, the only way we'll really challenge that is by having other ideas. What really throws this theory out for me however (And I admit, I can't view the page, it's been /.ed) was that most of Earth's fissle material is in the crust, not the core. So any 'deep explosion' would have to have been in the crust or mantle, not the center.
      • by Red Flayer ( 890720 ) on Thursday December 11, 2008 @10:26AM (#26075253) Journal

        What really throws this theory out for me however (And I admit, I can't view the page, it's been /.ed) was that most of Earth's fissle material is in the crust, not the core.

        That may be a bit of a chicken-and-egg problem. Maybe the fissile material in the core was exhausted in the runaway reaction, or in later reactions within the core (perhaps critical T&P exist in the core)... this seems plausible to me if, as with the crust, materials in the core were isolated and concentrated via geologic processes.

        It's also possible that the geological processes that occured over the past 4 Bn years have caused the fissile materials to accumulate in the crust instead of the core.

      • most of Earth's fissle material is in the crust, not the core.

        Citation? Because most fissile material is in the mantle, not the crust.

    • by mcgrew ( 92797 ) * on Thursday December 11, 2008 @09:55AM (#26074795) Homepage Journal

      My problem with it is simple that the impactor idea seems to fit all the data so well I think it's unlikley to be wrong.

      Further on they say that the impactor theory doesn't exactly fit the data. I'd blockquote, but I'm stuck on page three, I think we slashdotted it.

      They give several reasons; one is that the object would have had to hit at a precise angle to become the moon and not completely vaporize the earth. Another is that the object would have had to have been formed very near the earth; they calculate from the moon rocks it would have had to be between Venus' and Mars' orbits.

      • by Maury Markowitz ( 452832 ) on Thursday December 11, 2008 @10:07AM (#26074967) Homepage

        > 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

      • by CheshireCatCO ( 185193 ) on Thursday December 11, 2008 @10:11AM (#26075021) Homepage

        For the first point, it's not all that unlikely. (I don't know of any simulations that show that the impact would destroy the Earth, but you do need a specific range of impact angles to blow material off into orbit.) Remember, there were numerous collisions in that epoch, even between fairly large objects.

        As to the second point, I call BS. The moon isn't made of the original material of the impactor. If the authors say it is, they're showing that they don't understand the theory that they're deriding. The Moon is made (principally) of the Earth's mantle. That's why the giant impact theory is so appealing, it explains the compositional similarities.

        (That said, I seem to recall simulation work from about a decade ago that indicated that ALL the terrestrial planets had more or less the same composition since the planetesimals would be well-mixed in this region.)

    • by Rolgar ( 556636 )

      My old high school science teacher used to talk about how the volume of the moon was similar to the volume of the Pacific Ocean. I don't know if he was trying to imply that indicated where such an impact would have taken place, but since the impact is speculated to have happened over 4 billion years ago, and Pangaea existed two and a half million years ago, the one cannot have anything to do with the other, at least not directly.

    • There are some theories that Cruithne was Earth's second moon. So maybe the early Earth had two moons?

  • by tchiseen ( 1315299 ) on Thursday December 11, 2008 @09:43AM (#26074603) Homepage
    I thought that a number of scientists had run simulations explaining the earth/moon systems creation via a collision. I even saw it on TV on a special narrated by Tony Robbins, so it MUST be true!
  • The Moon! (Score:3, Funny)

    by Anonymous Coward on Thursday December 11, 2008 @09:43AM (#26074613)

    The Moon is a secret Italian conspiracy to spy on, undermine, infiltrate, and subvert America. That's why it is always in OUR sky -- ever wondered about that? How come Mexicans and Chinese don't get the Moon? Because they are in league with the nefarious Italians against our Great Fatherland.

  • by Waffle Iron ( 339739 ) on Thursday December 11, 2008 @09:46AM (#26074655)

    We all know that if there were a nuclear catastrophe of this magnitude, then the whole planet would be hurled through space at such speed that each week we would encounter a new alien race, group of outcasts, or supernatural being. Seeing as the earth is still in its stable orbit around the sun, we can conclude that this must not have happened.

  • Or maybe (Score:3, Funny)

    by eclectro ( 227083 ) on Thursday December 11, 2008 @09:46AM (#26074661)

    It was caused by aliens driving 737's and dropping nukes into volcanoes.

  • by mcgrew ( 92797 ) * on Thursday December 11, 2008 @09:47AM (#26074673) Homepage Journal

    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 [slashdot.org] before; it's the study of rocks.

    The term "georeactor" [wikipedia.org] 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.

  • by OldeTimeGeek ( 725417 ) on Thursday December 11, 2008 @09:49AM (#26074695)
    ...but not completely. The nuclear waste that caused the moon to be torn away were stored HERE! A cautionary tale?
    • From TFA (Score:4, Interesting)

      by mcgrew ( 92797 ) * on Thursday December 11, 2008 @10:09AM (#26074997) Homepage Journal

      I know you're joking, but

      In a major breakthrough reported in the U.S. journal Science in 2005, Earth scientists Maud Boyet and Richard Carlson of the Carnegie Institution in Washington DC, concluded that both a partition between the Earth's mantle and core, and another within the mantle, formed within 30 million years of the planet being born.

      This internal partition isolated the lower mantle, the D''-layer, from the rest of the mantle. Boyet and Carlson arrived at their conclusion by investigating the rare earth elements samarium (Sm) and neodymium (Nd). Samarium-146 is a radioactive element that decays relatively speedily, with a half-life of 103 million years, to neodymium-142.

      At present hardly any samarium-146 is left on Earth. Theoretically, terrestrial rock should contain just as much neodymium as the primordial material from which the Earth was formed - samples of which sometimes still reach the Earth in meteorites.

      But the researchers discovered something odd. Rock from the Earth's mantle contains more neodymium than these meteorites. The only conceivable explanation is that samarium was distributed unevenly throughout the planet, because the overall concentration should be equal to that in meteorites.

      But where can this neodymium-poor rock be? Not in the Earth's core, because neither samarium nor neodymium can bond chemically to iron. That only leaves the D''-layer. This chunky boundary layer between core and mantle must be low in neodymium.

      Boyet and Carlson discovered that the Moon has a peculiarity too: rocks that are just as rich in neodymium as the Earth's mantle. This makes the impact hypothesis very improbable indeed, according to van Westrenen.

      "Considering that at this giant impact 4.5 billion years ago the Earth's core and Theia's core fused, it is most improbable that isolated layers deep within the planet survived the impact. Yet this is what the data from Carlson and Boyet suggest."

      Carlson was candid about this over the telephone: "Our data show a strong similarity between terrestrial and lunar rock, but there is no good explanation for that at all."

      How the impact with Theia took place, and how the D''-layer survived this impact while the Earth's core fused with the core of the impactor, is beyond Carlson's comprehension as well.

      • There is the possibility that the impactor that is theorized to have created the moon formed from the same elemental "soup" as the earth. The planetary disk around the young sun may not have been 100% homogenous in these metals (we know it wasn't homogenous in terms of volatile elements and chemicals). Since the impactor very likely formed in the same region as the earth it should have had a very similar composition. The meteorites we see today are not necessarily representative of all the regions in the

    • by PolygamousRanchKid ( 1290638 ) on Thursday December 11, 2008 @11:27AM (#26076181)

      So, as soon Yucca Mountain gets tanked up, the Earth might get another moon?

      That would be cool!

      Less so, if you live in what used to be Nevada.

      Ah, the joys of Space 1999 Physics! Truly worthy of an Ig Nobel!

  • As /. causes a nuclear explosion on cosmosmagazine.com preventing anyone from RTFA
  • by 0xdeadbeef ( 28836 ) on Thursday December 11, 2008 @09:50AM (#26074717) Homepage Journal

    If the moon were real, it would have been created by God. Clearly a large ball of rock is the sign of an intelligent Creator, if it were there.

    • by MikeBabcock ( 65886 ) <mtb-slashdot@mikebabcock.ca> on Thursday December 11, 2008 @09:59AM (#26074839) Homepage Journal

      Christian-minded skepticism would sound a lot less idiotic (no offense to those of you who can't stand that), and something like:

      Why do we think this might have happened? Because it might be possible. Do we have any proof of it? None whatsoever. Does it seem likely or probable? Not enough data. Could the moon have been spontaneously created by an infinitely powerful being instead? Sure.

      • by db32 ( 862117 ) on Thursday December 11, 2008 @10:22AM (#26075183) Journal
        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 [wikipedia.org] and Ken Miller [wikipedia.org] 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.)
  • Nuclear Reactor (Score:5, Interesting)

    by heavygravity ( 160241 ) on Thursday December 11, 2008 @09:54AM (#26074779) Homepage
    Can't get to the article, but - if you haven't heard of this before, it's pretty cool: the Oklo Natural Fission Reactor [doe.gov] in Gabon. And while you're at it, you can read about how this natural reactor has scientists rethinking [wordpress.com] how constant the fine structure constant [wikipedia.org] really is.
  • LHC (Score:3, Funny)

    by mevets ( 322601 ) on Thursday December 11, 2008 @10:07AM (#26074971)

    version 0.9 ?

  • by Ancient_Hacker ( 751168 ) on Thursday December 11, 2008 @10:12AM (#26075027)

    I can't get to TFA, but it seems mighty unlikely to have that much fissile material just so happen to gather together, and not be poisoned by cadmium, boron, lead, or other neutron absorbers, and have it stay together and not have a negative temperature coefficient slowing it down, and not form bubbles and geysers and other instabilities, and have it push asymmetrically in one direction, for many hours (cf: speed of sound). Wayaaay too many things to believe before breakfast.

  • ... we can't have nukler power. You don't want there to be two moons, now do you? What would you do with two moons????
  • by CheshireCatCO ( 185193 ) on Thursday December 11, 2008 @10:17AM (#26075107) Homepage

    As noted, the site is Slashdotted so I can't read it straight up. That said, this doesn't make sense to me. A large explosion on the Earth's surface wouldn't launch material into Earth orbit unless it were launched at a very precise angle (probably nearly horizontal). The authors (based on previous comments) complain that the Giant Impact hypothesis requires a finely-tuned impact angle, but what about their model? I'd expect an explosion to blow material almost radially outward. To posit that you'd get the finely-tuned launch angle from their model seems much more of a stretch than that an impact should strike a glancing blow (especially when we don't know how many similarly-sized impactors hit with the wrong conditions and were simply absorbed).

    Also, note that you need to loft a lot more material than just the Moon's mass to make the Moon. it's not an efficient process, a lot (most?) of the material rains back down on the Earth. It has to, it starts out in an orbit that intersects the Earth after all.

    • Re: (Score:3, Insightful)

      Not sure if the article addressed this, but another point is that you'd have to assemble the fissionable material very carefully since you need to get it super-critical, but not have any of it blow too early, before you have enough. It's the classic bomb-making problem, only without anyone to supervise it.

  • by Wolfger ( 96957 ) on Thursday December 11, 2008 @10:39AM (#26075453)
    Oh, wait... it is. Nevermind.
  • by elzbal ( 520537 ) <elzbal@yaEEEhoo.com minus threevowels> on Thursday December 11, 2008 @10:41AM (#26075489) Homepage
    Slashdotted due to runaway nuclear reaction. Mirror here: Birth of the Moon: a Runaway Nuclear Reaction? [spotlynx.com]

    (Or should that be a runaway Slashdot reaction?)
  • by Arancaytar ( 966377 ) <arancaytar.ilyaran@gmail.com> on Thursday December 11, 2008 @10:59AM (#26075731) Homepage

    It's the mother of all core dumps!

  • by dpbsmith ( 263124 ) on Thursday December 11, 2008 @01:05PM (#26077791) Homepage

    It's really not the same at all, but the article did call this story immediately to mind.

    "Blowups Happen" is a classic 1940s SF story about a future in which society is total dependent on nuclear power plants. The engineering theory behind them shows that they are intrinsically safe and cannot blow up like a bomb. Then someone discovers that there is a false assumption in the equations and that, in fact they can blow up like bombs.

    Meanwhile, an expert in the theory of lunar formation has concluded the lunar craters cannot have been formed by meteor impact, because of the "rays." There had to have been enough energy to "crack an entire planet." The only possible explanation, he says, is that the Moon was once an inhabited planet with an atmosphere and that "Here at Tycho was located their main power plant, and here at Copernicus and Kepler, on islands of the middle of the great oceans, were secondary power stations."

    In other words, not only can they blow up like bombs, but that is what reduced the Moon to its present airless, lifeless, cratered and cracked state.

    As I say, that's a completely different theory from the one being discussed. Nevertheless, I would bet a nickel that at least one of the authors of that article had read "Blowups Happen."

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