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Closer to Deducing the Origin of the Moon 265

eldavojohn writes "A giant explosion on the sun in January of 2005 allowed SMART-1 (a European spacecraft orbiting the moon) to detect what elements the moon is made up of based on the X-rays from the sun's explosion. This allows scientists to speculate on the moon's origins while seeing data from all over the moon as opposed to the core samples we have collected and returned in the past. From the article: 'Scientists responsible for the D-CIXS instrument on SMART-1 are also announcing that they have detected aluminium, magnesium and silicon. "We have good maps of iron across the lunar surface. Now we can look forward to making maps of the other elements." said SMART-1's Principal Investigator.'"
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Closer to Deducing the Origin of the Moon

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  • Moo (Score:5, Funny)

    by Chacham ( 981 ) * on Monday August 21, 2006 @12:50PM (#15949443) Homepage Journal
    Oh man, you can bet that looking into the moon or bits of it will have you coined as a loony, figuring out its "source" is just plain cheesy, and given its size is anyway having to force a choice between the light and dark side.
    • So, if the moon falls off a table, does it land on its light or dark side?
  • by Conspiracy_Of_Doves ( 236787 ) on Monday August 21, 2006 @12:51PM (#15949457)
    Don't believe me? Go to google moon [] and zoom all the way in.
  • Valuable metals? (Score:5, Interesting)

    by Ed Avis ( 5917 ) <> on Monday August 21, 2006 @12:53PM (#15949465) Homepage
    What are the odds that the moon turns out to be composed partly of gold, or platinum or palladium? Would moon mining be profitable?
    • by LiquidCoooled ( 634315 ) on Monday August 21, 2006 @12:55PM (#15949484) Homepage Journal
      If the moon is made of palladium would the DMCA prevent mining?
    • Only if it had large oil deposits. I'm thinking of selling my gold coins for gas money!
    • Re:Valuable metals? (Score:4, Informative)

      by misleb ( 129952 ) on Monday August 21, 2006 @01:01PM (#15949523)
      Unless you can pull out huge chunks of the metals at one go without much work or processing, I seriously doubt it. Just getting a couple people on the surface to walk around a bit is massively expensive... forget about a sustained effort with mining equipment, life support and everything else you'd need.

      • by Khyber ( 864651 )
        You won't need much work - moon's gravity is far less than that of Earth so extracting and packing large boulders of stuff without machinery then becomes possible. Just pick up a boulder, and move.
        • Re: (Score:3, Interesting)

          by misleb ( 129952 )

          You won't need much work - moon's gravity is far less than that of Earth so extracting and packing large boulders of stuff without machinery then becomes possible. Just pick up a boulder, and move.

          Are you seriously suggesting that humans *manually* mine the Moon? You've got to be kidding. Yeah, I'm sure astronauts are going to be lining up to train for years just to go to the moon to work as slave labor because hauling machinery up there is too expensive. Even in the worst of times, humans have had beasts

      • Just getting a couple people on the surface to walk around a bit is massively expensive... forget about a sustained effort with mining equipment, life support and everything else you'd need.

        Just use robots, remote controlled where neccessary. We can already build machines that can traverse the moon, we can build machines that can mine and extract ore with little human intervention, automated refineries are easy, and power the whole thing with lovely naked solar radiation! The first thing they build are

    • by Tweekster ( 949766 ) on Monday August 21, 2006 @01:04PM (#15949549)
      Actually it is a break even proposition for gold. is at about 625 per ounce...16 ounces per pound, 10,000...the current cost per pound to send something into space ( i dont know what the cost to retrieve it per pound would be, to send it back though) I would assume it is less expensive to send back, time is not exactly a factor, or life support systems etc.

      It is difficult to calculate because I couldnt find much info on sending stuff back from the moon, I am willing to bet it is quite a bit cheaper. But the infrastructure on the moon etc ruins any math. It would be break even for gold to be sent into space...and retrieving it would probably be long term profitable. (providing you can find enough gold)

      Platinum is 1200 dollars per ounce making it much more possible, if sufficient quantities could be found.

      The cargo ship would probably be reasonably equipment on board, doesnt need to be very fast, just a computer control system and the rockets etc necessary to bring it back in. Could be an interesting proposition.
      • Re:Valuable metals? (Score:5, Informative)

        by 'nother poster ( 700681 ) on Monday August 21, 2006 @01:07PM (#15949562)
        12 oz. per lb. Precious metals are mesured in troy oz, not avoirdupois.
        • Re: (Score:3, Insightful)

          by Red Flayer ( 890720 )
          12 oz. per lb. Precious metals are mesured in troy oz, not avoirdupois.
          1000 grams per kilogram. People calculating the costs of getting things off of and onto Earth use metric, not archaic.

          Or they learn a very expensive lesson.
          • Re: (Score:2, Informative)

            He was talking about the precious metals value. That is in troy oz still. If you, or he, want to take them someplace you do the conversion to those upity new metric things.

            "My car gets forty rods to the hogshead, and that's the way I likes it!" - Grampa Simpson
          • People calculating the costs of getting things off of and onto Earth use metric, not archaic.

            Or meters instead of feet to get things onto Mars...oops.

      • Regardless of the economics (which you discussed quite well, I think), the moon should be very metal-poor if it was formed via collision. The heavier metals "sank" towards the core when the earth was molten. The collision knocked off the top, lighter material, like silica.
        The density of the moon is 3.35 g/cm^3 whereas the density of the earth is 5.51 g/cm^3.
        • That is average density. For all we know, there are large easy to get deposits of valuable material. Until we start really exploring it, we will not know.

          OTH, if anybody is betting on the moon having cheap valuable minerals, well, they are making a very long bet.
      • Re: (Score:3, Informative)

        Gold is at about $625 per troy ounce or 480 grains, or about $1.30 per grain. A troy pound is 12 ounces or 5760 grains, whereas an avoirdupois pound, used in launch masses, is 7000 grains, so one avoirdupois pound of gold is worth about $9100.

        I suspect retrieving dissolved gold from the ocean would be more cost-effective.
        • Of course, the moon would have much lower launch costs than we do. So if we sent a minimal amount of automated equipment, I would think that it might be doable. In particular, if the moon launches using a rail system, then I think that the launch of material is dirt cheap.
        • by Chacham ( 981 ) *
          so one avoirdupois pound of gold is worth about $9100

          Actually, it's about 1516, because things on the moon weighs 1/6 of what they do here. *And* if you mine the gold, you are removing from its mass, making it weigh even less. So, i'd adjust it to an earlier 1500s.

          Unfortunately, in the 1500s, exploration of the moon would get you a marked as a looney, and a looney isn't worth very much, especially outside of Canad eh?

      • by kthejoker ( 931838 ) on Monday August 21, 2006 @01:21PM (#15949652)
        Would they actually have to ship it back?

        I mean, nobody has seen the gold in Fort Knox in years, but it's been traded around left and right. Plenty of people are willing to pay for pieces of paper saying they own some gold - why not just prove it's there, stake a claim on it, and then sell it here on Earth?

        We can have an entire imaginary Moon economy! Awesomeness++!
        • by Belial6 ( 794905 ) on Monday August 21, 2006 @01:42PM (#15949784)
          You are aboslutly correct, and it seems that you would have the added benefit of being the most secure storage site on the plan... eh... in the solar system.
        • >Plenty of people are willing to pay for pieces of paper saying they own some gold

          Still a better deal than the green pieces of paper not even saying that!
          • Re: (Score:3, Insightful)

            by thefirelane ( 586885 )
            Still a better deal than the green pieces of paper not even saying that!

            I love gold people... at a fundamental level they don't realize that both paper and gold are completely useless unto themselves, and are only worth what people will pay for it. If you really worry about your well being in an apocalypse, buy canned food and ammmo, because that is all that will be worth anything.
            • I realize very well that everything is worth only what people are willing to pay for it, however, I don't see how it undermines my original statement (it was mainly a joke, btw), I still think it's a better deal. Exhibit A. [] Exhibit B. [] Sorry I couldn't find some pretty graphs for both of them.

              In the apocalypse scenario, my checklist would look like this:
              1. Diesel fuel
              2. Diesel power generator
              3. Computer, laptop
              4. Food (could be combined with abouve, there's food in my keyboard)
              5. Ammo

              Hmm, maybe it shouldn't be an ordered l

        • Re: (Score:3, Funny)

          by thefirelane ( 586885 )
          why not just prove it's there, stake a claim on it, and then sell it here on Earth?

          Fine... I've just claimed all the gold on the moon, care to buy it from me? I'll start the bidding at $1,000 and you can have first dibs.

          Using that logic, why even mine it here on earth?... eventually we'd wind up with some wierd paper notes completely disconnected from actual known gold amounts... crazy!
      • by EatHam ( 597465 )
        It would be break even for gold to be sent into space

        I'm no scientist, but I'm having a tough time thinking how there would be any sort of monetary advantage to firing a bunch of gold in to space. Retrieving it, sure, but sending it out?
      • Re: (Score:3, Interesting)

        by east coast ( 590680 )
        Also consider refinement and mining costs. We're not going to find this stuff in bar form just laying on the surface. It's going to raise the costs significantly, I'm sure.
        I wonder how much gold would need to be brought to earth to effect the market value of gold. There's a chance that, in order to profit, a company would need to mine so much gold that their returns would faulter on a decline in gold prices due to a surplus.
      • With the moon, why not build a space elevator? It would have to be much, much cheaper and easier than doing so on Earth. We probably have the tech to do it right now. Given that it would be useful for things like exploration and research as well, the cost of building such a space elevator could be written-off as far as a mining project goes.
        • Umm, because using a space elevator to put gold into orbit around the moon wouldn't be very profitable?

          Or were you suggesting that the space elevator connect a point on the moon with a point on the Earth? If so, I recommend you go out one night and watch the moon for a few hours. You may notice a slight problem with your plan.

      • by rho ( 6063 )

        Also there's the inflation issue. When the New World was opened up and all that Aztec gold was shipped back to Spain, prices skyrocketed. If you dump a ton of Moon gold on the Earth, the gold won't be worth $625/oz.

      • Actually, I've heard that it costs $10-20k (depending on the type of rocket used) per kg (not lb.) to lift a payload to LEO. It should therefore cost at least that much, probably somewhat more, to lift all the way to the moon, which is considerably farther away than LEO.

        How much it would cost to *collect* and *return* a mined cargo is a completely different matter from how much it would cost to lift a vehicle up there to retrieve it, and these costs likely dwarf the lift costs of the vehicle outbound from
    • Re: (Score:2, Insightful)

      How is this interesting? This is stupid, the elements are pretty much distributed the same way across the universe; trace elements like palladium are rare everywhere.
      • by Sparr0 ( 451780 ) <> on Monday August 21, 2006 @01:11PM (#15949580) Homepage Journal
        Yeah. Everyone knows Earth has just as much Hydrogen, relative to its mass, as Jupiter. Oh.
      • Re: (Score:2, Insightful)

        And you know this for a fact how? Just curious. I agree it's very unlikely that there are clumps or veins of palladium on the moon, but it's not impossible. The K-T boundary layer is significantly higher in several trace elements, so it is surmised that they came from an asteroid that hit the earth, so at least that asteroid had much higher concentrations. Why couldn't Luna?
      • by Tycho ( 11893 )
        Yes, I've always kind of wondered about the wisdom of trying to obtain any rare element from space. To make a certain element economical or even possible to mine on the Earth the element has to be concentrated somehow. On the Moon there are fewer ways that elements can be concentrated. There was never liquid water on the moon to erode and transport an element. For that matter there is little to no variation in the types of rocks, there is no granite on the Moon. The lack of granite is due to how granit
        • I agree with what you said as to the moon; however, there are asteroids that have been identified that are quite concentrated in various metals. If we could come up with a technically feasible way to move some of the more modest ones into a high earth orbit (perhaps a good application for a thermonuclear engine), they could even be processed much closer to home. A bonus if we can "capture" and process near-Earth asteroids that threaten our existence every so often.
      • by VENONA ( 902751 )
        This is Score:2, Insightful? Wow.

        On large scales, things will average out. In resource extraction, though, you care about *local differences*. You're saying you can dig a gold mine anywhere and get the same results. I think I'll side with the people who want to dig where the concentrations are. Duh.

        The more we know about the moon, the greater the possibility of finding a useful concentration of something. I'd bet that H3 concentrations would have a better shot at economic viability than any metal, but I've
    • Re:Valuable metals? (Score:5, Informative)

      by Denial93 ( 773403 ) on Monday August 21, 2006 @01:11PM (#15949577)
      No. The only unique property of moon ore is that it isn't inside such a big gravity well, so it is less expensive to move up into space. And unless something fantastically rare and useful can be found there, even the most prized minerals would only be attractive in massive amounts because you would first have to more the necessary equipment up there, not to mention transport capacity to get the stuff to any buyer.

      Only tourism and science are likely to be viable there in the foreseeable future. Big exception: if we unexpectedly manage to get automated construction from raw minerals to work, this could make industry on the moon so cheap it could become viable to start mining and export there. However, this isn't going to happen anytime soon, and when it does it will end capitalism as we know it anyway, so it is nothing you could base a business model on.
      • ... when it does it will end capitalism as we know it ...
        You underestimate the power of greed. The real question is how capitalism would adapt. My own view is that the patent system would probably be used to restrict use of the associated technologies to a privileged few, and thus ensure that the vast majority of the wealth produced continued to be distributed as it always has.
      • by c_forq ( 924234 )
        not to mention transport capacity to get the stuff to any buyer.

        Last I looked into the gold market, it is exceptionally easy to own gold without having any transported to you. I seem to recall the US government doing the same with silver, as evidenced by silver certificates.
      • Nobody has to actually mine the moon for valuables to have'em become dirt cheap down here on earth.

        The very prospect that the moon -could- be mined will make futures prices on valuables go down, and make'em less valuable here on earth---without ever even sending stuff up there.

        Imagine if they find 10x as much gold there as was ever mined on earth... without any mining there on the moon, the price of gold would drop.
      • Actualy, there's a second unique property of moon ore - absolutely no need what-so-ever to worry about the enviromental impact of mining it. That would likely have a pretty decent impact on the economics of moon-mining.
    • Its not made of gold, but if it was it would destroy the gold markets value. Anything that is actually up there would have to be worth more in actual intrincic value (energy, water, building materials) than the cost of setting up an operation. Someday we will definatly be mining the moon and other astroids for materials to build with, but I seriously doupt so called precious metals or gems will have much value in such a future.
    • Even though it's unlikely there will be significant precious metals on the moon, sending stuff back to Earth is relatively easy once everything gets up there in the first place. The trip from the Moon to the Earth is effectively "downhill."
      • Re: (Score:3, Informative)

        by R3d M3rcury ( 871886 )

        The trip from the Moon to the Earth is effectively "downhill."

        Yeah. But it's the brick wall at the bottom of the hill you have to worry about.

        To me, the tricky part of getting it here would be landing it. Sure, you can get it to the Earth fairly easily--Moon has low gravity, Earth has high gravity, etc. The problem to me is that you kind of need to arrange a soft landing for it. So you have to slow down, say, 1,000,000 pounds traveling at, say, 20,000 MPH and set it down gently on the Earth.

        That's gonna

    • Re: (Score:3, Interesting)

      Even if the cost of transporting Moon gold to Earth is zero, it will not make goldmining profitable in Moon. It would just make gold mining unprofitable on Earth.

      For example Amethyst used to included in the list of cardinal gems, (i.e. diamond, ruby, sapphire and emerald). But huge discoveries in Russia and South America has erorded its value to almost that of costume jewellery. On my way to work I pass a shop window displaying an Amethyst geode some three feet long and 1 feet across, partially opened. M

      • For example Amethyst used to included in the list of cardinal gems, (i.e. diamond

        I assume cardinal gems are gems whch have value because they are naturally rare? If so, diamonds do not qualify as a cardinal gem, despite popular myth. Diamonds are both common and easy to make by man. The only thing making diamonds scarce is the maket manipulations by the like of the De Beers cartel. In other words, diamonds are artificially made scare to maintain their value.

    • Not to be a wet blanket, but: No. I really do wish we could go exploring the solar system - with giant spinning spaceships made of lead, titanium and steel. But it just isn't going to happen. We won't have the energy to get there. The USA going to the moon in the late 60s early 70s is the Modern equivalent of the Pyramids.

      In 1970, USA oil extraction was at its peak. We had energy to burn, literally.

      We're not going to put many more, if any, people on the moon - and we're not going to put people on Mars,

      • You suck...because you're probably right. Damn you! No off with you to find some candy and babies... ;)

      • by Ed Avis ( 5917 )
        I don't get it. Surely a trip to the moon doesn't use more energy than a thousand domestic aeroplane flights, that is, not very much compared to our total energy use each year. What are the numbers here?
      • by VENONA ( 902751 )
        I guess that depends upon whether you're essentially optimistic or pessimistic.

        Assuming the human race face some sort of doomsday scenario (a rather large assumption), my guess is that we'll eventually see one or more disruptive technologies which will provide cheap energy in some form. Whether that comes from advanced solar (maybe something a lot better than the 20% efficiency we can get from cells now, maybe thin films instead of cells), carbon nanotubes which allow a space elevator (hence maybe power sat
    • Three words for you man: Lunar Space Elevator. All you would need then is an economical way to do the mining -- keeping in mind that solar power works like a hot damn on the moon thanks to its thin atmosphere and lack of climate. You could probably only run the site during the times when the moon faced towards the sun (it would presumably be solar-powered), but that still provides you with a lot of mining time.
  • by crazyjeremy ( 857410 ) * on Monday August 21, 2006 @12:53PM (#15949475) Homepage Journal
    I thought God made it. Oh well, learn something every day.
  • by bsa3 ( 200 ) <brad.facefault@org> on Monday August 21, 2006 @12:57PM (#15949495) Homepage
    What's now posing as the Moon is really the Fourth Imperium Utu-class planetoid Dahak, hull number 177291 -- the original was destroyed 51,000 years ago.
  • origins? (Score:3, Informative)

    by PresidentEnder ( 849024 ) <wyvernender@gmai[ ]om ['l.c' in gap]> on Monday August 21, 2006 @01:01PM (#15949521) Journal
    Forget the origins of the moon. The moon's here. What I find interesting is that they're mapping the elements on the moon, and where they are. This gives us a map of where to go mine. They already said they found iron; eventually, someone will find a way to make moon mining more monetarily motivational.
    • by saskboy ( 600063 )
      I'm just glad we didn't build a giant XRay machine to examine space objects, when there's a free source in the center of the solar system happy to provide the rays. 'Cause I'd hate to see the XRay bill otherwise.
    • They already said they found iron; eventually, someone will find a way to make moon mining more monetarily motivational.

      I think that will happen when we have appropriate infrastructure on the moon to make things up there rather than down here.

      I'm not all that convinced that it will ever be economically feasible to send raw ore from the Moon to the Earth in order to build stuff down here, versus mining the ore here on Earth. Heck, consider Pittsburgh. It's close to iron ore (raw material), close to the oce

  • by drewsup ( 990717 ) on Monday August 21, 2006 @01:11PM (#15949581)
    Where are the vast deposits of cheese Grommit, the Cheeeeeeese!
  • More Details (Score:5, Informative)

    by writerjosh ( 862522 ) on Monday August 21, 2006 @01:15PM (#15949601) Homepage
    Here's a few more details about this Impact Theory:

    "The basic idea is this: about 4.45 billion years ago, a young planet Earth -- a mere 50 million years old at the time and not the solid object we know today-- experienced the largest impact event of its history. Another planetary body with roughly the mass of Mars had formed nearby with an orbit that placed it on a collision course with Earth. When young Earth and this rogue body collided, the energy involved was 100 million times larger than the much later event believed to have wiped out the dinosaurs. The early giant collision destroyed the rogue body, likely vaporized the upper layers of Earth's mantle, and ejected large amounts of debris into Earth orbit. Our Moon formed from this debris."

    Plus, this page has a really cool rendering of the Impact: tions/question38.html []
  • These scients know that you need to understand the origin of the moon, in order to destroy it.

  • by stupidsocialscientis ( 689586 ) on Monday August 21, 2006 @01:42PM (#15949780)
    Well of course the "lunar landing" rocks were similar to Earth's, they were from Earth. It is accepted fact that we never went to the moon. The present analyses simply add more support to this fact. Oh, and if you want to know my credentials, as IANAA (the last part can be astronomer or astronaut- take your pick) I watch Fox, and that is where I get all my current information, everything else is in my Bible. You can't imagine how much I have saved on bookcases and moving expenses over the years by only reading and owning one book.
  • ummmmm... (Score:2, Funny)

    by night_flyer ( 453866 )
    Genesis 1:16
    For God made two great lights, the sun and the moon, to shine down upon the earth. The greater one, the sun, presides during the day; the lesser one, the moon, presides through the night. He also made the stars.
    • Well, not all the stars. There was this King Trishanku, who wanted to ascend to the heavens with his body. So he commissioned the sage Vishwamitra to perform the sacrifices and the rituals. But as King Trishanku was rising towards the heavens, Indra, the Lord of Heavens, struck him down with his weapon Vajrayutha. Vishwamitra suspended Trishanku in mid air. He eventually became a galaxy known as the Trishanku Mandala. So you see, atleast some stars were made by Sage Vishwamitra.

      For more details []

    • I call Shenanigans!

      Merodach rested a while, gazing upon the dead body of the dragon. He divided the flesh of Ku-pu,
      and devised a cunning plan.

      Then the lord of the high gods split the body of the dragon like that of a mashde fish into two halves. With one half he enveloped the firmament; he fixed it there and set a watchman to prevent the waters falling down.
      With the other half he made the earth.
      Then he made the abode of Ea in the deep, and the abode of Anu in high heaven. The abode of Enlil was in the air.

    • Which is about as relevant to this conversation as a recital of the Mon-Chi-Chi themesong.

      Possibly even less, because Mon-Chi-Chi's were oh so soft and cuddly.
    • Notice the gross egocentric position of the writer of this poetry. The stars are an after thought as indicated but the, oh by the way, parenthetical status in the verse. However as we now know the stars (ie the universe) are of such a grand scale compared to puny earth. This should be tip off for the decerning reader; but nooooo some have to take this poetry (and it is good poety) as a science textbook.
  • Whatever happened the TONS of moon dust that the USA supposedly has in storage somewhere? Doesn't that tell us what the Moon is made of? And... if we can bring back TONS of Moon dust then we could certainly bring back TONS of Gold! --Matthew Wong []
    • by Khyber ( 864651 )
      Well, there's the conspiracy that says we never landed upon the moon to begin with.

      However, a far more likely reason is that we didn't go down far enough with our core samples, and this nice massive burst of x-rays from the sun gives a chance to look deeper into the moon where we couldn't before.
  • If you've seen the widescreen version of The Fifth Element, you see that the moon is a dead sphere of "pure evil". In the 4:3 version, you don't see the first moon and hence can't really make the connection... (cropped content SUCKS).

  • Heavy Weather (Score:3, Insightful)

    by delire ( 809063 ) on Monday August 21, 2006 @02:09PM (#15949989)

    'Origins' aside, it's mining companies (and venture capitalists with an eye for off-world enterprises) that will be most interested in these findings, lending the idea that they are likely funding some of this research.

    While this may sound absurd, it's perhaps worth asking: How much rock do you have to move off the Moon before the Earth starts seeing climatic changes as a result? Any one know of research into this area? Given the blatant denial certain first word countries have evidence in the face of an eroding Ozone layer, let's hope the moon isn't laden with valuable metals, ores and other resources..
    • by spitzak ( 4019 )
      I assumme you are talking about pollution from the spaceships necessary to do this. The actual transfer of matter from the moon to the earth in the quantities that we could do even if we put 100% of all human's efforts into doing it is unlikely to effect things one bit.

      My guess is that if some highly unlikely situation makes it profitable for independent prospectors to build their own ships and go to the moon to mine it, and there is a gold rush of some sort of these, then we should worry. Until then, howev
  • Accepted Theory (Score:3, Informative)

    by TheZorch ( 925979 ) <thezorch@gmail. c o m> on Monday August 21, 2006 @02:22PM (#15950079) Homepage
    Its an accepted theory that the Moon originated from the Earth.

    Sometime in Earth's early history, before the formation of life, a large Mars-sized object probably collided with the Earth throwing off a massive amount of material.

    For a time its believed the Earth might have had a Saturn-like ring system until tidal/gravitational forces caused the material to begin clumping together into what would one day be the moon. Its also likely that some material rained back down on the Earth. Supporting this theory is the well known fact the Earth has a very faint, barely detectable, ring.
  • ..i just want to know who the bastard is that carved "CHA" into it!
  • The findings make sense for the theory which states that an off-center impact of a largish planetesimal merged with the nascent earth 'momentarily', then threw off a globule roughly the same size as that planetesimal. It makes sense if you consider that the earth's mantle is made primarily of molten silicate rock and light metals, so an impact which 'punctured' the earth and 'kept on going' would have passed through the mantle and taken the mantle rock with it. The moon, if the samples brought back are an
  • will we go to war against the green cheese eating moon aliens?

Things equal to nothing else are equal to each other.