The extraordinary back of the Moon

By Phil Plait | March 12, 2011 7:00 am

Remember last month when I posted that incredible super-hi-res image of the Moon’s near side? A lot of folks asked if an image of the far side were coming soon.

Ask, and ye shall receive.

Holy Selene! Click to enlunanate.

This amazing mosaic is from the Lunar Reconnaissance Orbiter, circling the Moon from a height of a mere 50 km (30 miles) and mapping that entire world. This image is comprised of a whopping 15,000 images from the Wide Angle Camera — yegads! — and shows the side of the Moon we can never see from home.

It looks really different than the near side, doesn’t it? It’s almost entirely craters, while the side we see is dominated by huge lava filled basins called maria (Latin for "seas"). Why is that? Well, it’s known that the crust on the near side is thinner, so it’s easier for big impacts to have punched holes in the crust and allowed magma to bubble up (this was billions of years ago when the inner Moon was still molten).

But why does one side have a thick crust and the other thin? No one knows. Interestingly, it’s probably tides from the Earth that forced the Moon to have this asymmetry line up with us. The Moon causes tides in the Earth, but the Earth does the same for the Moon, and the tides we create on it are much more powerful, since the Earth is far more massive than the Moon. Tides like to stretch things, and they also like to have any imbalance settle along the Earth-Moon line.

[UPDATE: Some folks were questioning my next claim, that the far side of the Moon is heavier (technically, has more mass) than the near side. The thing is, I think they're correct! The crust is thicker on the far side, but it's made of less dense material than the stuff below it. That means the half of the Moon farthest from the Earth is slightly less massive than the half facing the Earth! Or, in other words, the center of mass of the Moon is a bit closer to the Earth than the physical center of the moon (see here, and scroll down to the bit about the Moon's crust). In other other words, I was wrong. Thanks to everyone who pointed this out to me. Ironically, just tonight I was helping my daughter with her science homework. The topic? Buoyancy and density! That helped me understand my mistake here. Anyway, I've struck it through; I'll keep it up so people see the mistake I made. What I said about common sense is still right, though, and is doubly true here for me!]

You might think the heavier side would settle toward the Earth, since that’s "down", but in fact tides don’t care if the heavier side is pointed directly toward the Earth or directly away, as long as it’s on the Earth-Moon line. In our case, the heavier side of the Moon points away from us.

Weird. But while the Universe has to follow the laws of physics, it doesn’t always have to follow our common sense.

You can explore the Moon yourself; the folks at LRO also released this very cool picture of the Moon as seen from all sides, in 60° increments. Scanning over this is fascinating. I’m used to looking at close-ups, so seeing the overall picture is very, very cool.

And useful. Maps like these will be used to gauge where to send more probes, and, eventually, people. I can’t help but wonder: in a few decades, will school children have to memorize the locations of Mare Orientale, Copernicus, and Rupes Recta… before taking a field trip there?

Image credit: NASA/GSFC/Arizona State University


Related posts:

- The extraordinary face of the Moon
- Lunar rock and roll
- Gettin’ high on the Moon
- There’s a hole in the Moon!

CATEGORIZED UNDER: Astronomy, Pretty pictures

Comments (87)

  1. frag971

    Dat ass.

    … Sorry couldn’t resist. Great stuff!

  2. IronSky

    Where are the Nazis!?

  3. Just Wondering

    The closer side is thinner? Could centrifugal forces (often said to be fake, but a different way of representing the forces in action) have something to do with this? The moon was swinging around Earth fast enough to move molten rock to the outside?

    It got piled up on the outside because there was no rotation of the moon to spread the crust around.

    Granted, this would probably only work if the moon became tidally locked while it was still very malleable…..

    I could be missing something and end up horribly wrong, but… make sense to me….

  4. fatherdaddy

    I volunteer to chaperon the kids on that field trip.

  5. Bill-O

    But how’d the moon get there? How’d it get there? Can you explain that to me? How’d it get there? C’mon. C’mon.

    You pinheads.

  6. Its so different. I like our side better. Just a personal aesthetic preference. Not for any valid reason.

    I guess my common sense is off. I would have guessed the thicker side was the outside, kind of like the kid on the end of “crack the whip” getting all the energy and flying off. But I am not remembering my Newtonian high school science and cannot remember the name of the law or its rules.

    Anyway, clearly if that was the answer, smarter people than me would have figured that out, so I’m wrong.

  7. Oli

    Why are there so many craters at the Moon’s poles?

  8. jearley

    Great! Now, how about a shot of the Moon from over the poles? I’ve never seen any large scale photos from that perspective, and it would be cool.

  9. mln84

    BA> “In our case, the heavier side of the Moon points away from us.”

    Can someone expand on this? (BA, maybe a new post…) I thought the moon was nearly spherical. If so, and the crust was thinner on our side (as you said) wouldn’t that mean the core is off-center toward us? And if that is the case, isn’t the core more dense and therefore the heavier side is toward us? Is my problem in the “nearly” spherical bit or is there something else I’m missing?

    Thanks.

  10. DrBB

    Wait, is that the Supermoon??? Or just the regular one?

    Okay, sorry to carry my grumpiness over from a different thread. Utterly cool picture and thanks for posting it. One of those things where you’re pretty sure it’s just gonna look pretty much like the other side, no reason for it to be totally different you’d think, and then Wow, wait a sec…. the Far Side really is pretty strange!

    I’d like to echo @4 Oli’s query–I seem to recall hearing an explanation but can’t remember what it was. I wouldn’t mind hearing what the explanation is for the difference in the crust and “heaviness” of the two sides, too–something to do with being tidally locked and experiencing centrifugal effects…?

  11. Andrew W

    4. Oli
    The polar craters appear more prominent because the sun is at a low angle, so there are longer shadows, the photos selected for the mosaic all appear to have been taken at the local noon.

  12. Chris Merchant

    Business in the front, party in the back. The man in the moon has a lunar mullet!

  13. Bob Studer

    “I can’t help but wonder: in a few decades, will school children have to memorize the locations of Mare Orientale, Copernicus, and Rupes Recta… before taking a field trip there?”

    No, because by then, the way things are going, the current “lies” will probably have been replaced by Biblical Truth. Sheesh. 8-/

  14. hhEb09'1

    @mln84

    You’re right, more or less. It is not just the crust involved in the mass profile of the moon, but it’s been generally said that the heavy parts (mascons) of the moon are concentrated on the near side. And, it’s not along a line directly towards the earth. I’m not sure what the BA means. Perhaps he can explain, or give us a reference.

  15. Gjeff

    Dean Martin sang “When the moon hits your eye like a big pizza pie. That’s amore.”. That might explain the thin crust and thick crust options on either side. The toppings on the moon look interesting but are not that tasty. Perhaps what looks like craters are actually pepperoni slices.

  16. Robert S-R

    A cross section of the Moon along the Earth-Moon line would help me picture the crust as well, but I have a fair idea of what it might look like. I bet the lop-sidedness of the Moon is the result of the nature of the Moon’s formation (Mars-sized planet smashed into Earth, chunks coalesced and stayed in orbit). The fact that the “heavy” side is away from us doesn’t surprise me, since it sounds just like the force that causes high tides on both sides of the Earth even when the Sun and Moon are pulling the same way. (Am I close? I’ll be honest, I don’t understand the tide thing at all, but the two concepts sound similar.)

  17. John Paradox

    So the photo is being mooned by the Moon?

    J/P=?

  18. Thameron

    Here’s a question I’ve never seen the answer to. How long after the Moon’s formation did it become tidally locked? When was the last time a creature on Earth could look up and see that back side?

  19. Rodrigo

    Man, great stuff, but can I ask for a 3D full moon animation? Please? :D

  20. Don Q

    3D pictures of the moon? This would be as simple as a series of pictures with something less than 60 degrees separation like the ones posted here. I cant quite get the cross-eyed 3D thing to work with 60 degrees.

  21. sudeep

    i have never seen this picture

  22. Gary

    Moon has a front side, moon has a backside. You can’t explain that! :)

  23. Minda

    looks like moon covers earth from meteorites pretty well, the other side of moon really got hard hit over time. just a thought…

  24. Carson Myers

    I’d like to see this projected onto a flat map

  25. Elwood Herring

    @Thameron: I’m not sure but I’ll hazard a guess that the Moon became tidally locked well before eyes evolved in any animal; ergo us humans are the first ever to see the far side.

  26. Martha

    Hey the moon is round. Who are you to say it can even have a “back?” You scientists just think you know everything. : )

  27. colluvial

    I thought the reason there were more craters on the far side of the moon was because it’s less protected by the Earth.

  28. Liath

    Gjeff says
    “When the moon hits your eye like a big pizza pie, that’s amore.”

    I really wish you hadn’t said that. That blasted song will be floating around my brain for the rest of the day. It’s almost as bad as “Suddenly Seymore.”

  29. liath

    #23 Minda

    I think the earth got hit with as many meteors as the moon. We just eroded the craters and the moon never learned the trick of keeping an atmosphere.

  30. DrBB

    @26 Martha: sounds like you’re another refugee from the Supermoon thread. ;-)

    I’d like to endorse Gjeff’s opinion re pepperoni, but where are the anchovies? None, I hope. I hate anchovies.

    I do seem to recall that the thick/thin crust thing explains why the sides look so different: that the thinner crust could be penetrated by meteor strikes and magma (whatever the correct term is) flowed out to create the mares, evidence that the moon once had a molten core though it doesn’t any more. Correct? [oops, I see Phil addressed that--I should read the words as well as look at the pretty picture]

    Glad to have the answer/speculation about when it became tidally locked–I was wondering about that as well.

  31. Steve

    “I can’t help but wonder: in a few decades, will school children have to memorize the locations of Mare Orientale, Copernicus, and Rupes Recta… before taking a field trip there?”

    Unless the powers that be get their collective fingers out, I doubt whether school kids in the future will even know we went to the moon at all!

  32. Thameron

    @ 25. Elwood Herring

    I would imagine so since the history of life on Earth was dominated by one celled organisms for about 3 billion years or so and we multi-celled critters didn’t come on the scene until about 0.75 billion years ago or so. Feel free to jump in with the exact figures if you have them.

    It’s just that there seem to be certain points that them thar pointy headed scientists never give a figure for. The Earth is 4.5 Billion years old. We get that particular figure a lot, so when on that scale did the collision with the mars sized body take place? Before it started? After? If so how long after?

    How close to the Earth was the Moon when it coalesced? And of course when did it become tidally locked? I have not seen those figures/dates in my admittedly cursory travels. All I want is the timeline. Is that too much to ask?

  33. Bob H

    Actually, as mln84 pointed out, the core is heavier than the crust (that’s why the crust is on top) so the light side is the back side. Assuming the moon formed near the Roche limit and migrated to its current position then the backside would be more exposed to outlying moonlets and external asteroids than the front.

  34. Old Rockin' Dave

    Not quite on topic, but Liath, I often get songs stuck in my head, and what never fails to dislodge them is to listen to “I Fought the Law” by the Bobby Fuller Four. Sometimes I have to listen to it twice, but it always works.

  35. DrBB

    @36: Now that’s a great tip. I think William Gibson was the one who said the only way to get a bad media virus out of your head is to go focus on a worse one. I believe the recommended treatment involved the film “Surf Nazis Must Die,” so the aural equivalent might be, I dunno, ABBA or something. But “I Fought the Law”–now there’s an antidote I can get behind. And even if it doesn’t work, at least you’ve been listening to a mad wonderful kickass piece of rock history. Clash version’s not bad either.

  36. DrBB

    Here’s a relevant query though: every time I glance at the lower-res version here I get this really strong impression of a vertical line down the middle. There does seem to be a series of craters extending up from the south pole toward the center that are in a strongly linear arrangement, then some smaller ones going north that reinforce the impression. What’s up with that? A comet broken up like Shumaker-Levy and striking in rapid series? Or just my brain seeing order where there’s only chaos?

    ..adding, there are a couple other linear patterns, such as the one from about 11 o’clock at the upper left stretching down toward center at an angle pointed at about the 2-3 o’clock position. Wonder if any of this is “real” or just random?

  37. Nk_knight

    Definitely thought that there was suppose to be glass tubes that aliens lived on the dark side of the moon, right?

  38. JeffB

    @DrBB There are some distinct linear artifacts from the mosaic assembly that lie along that central vertical line. These are especially noticeable at the poles. Otherwise, there are so many craters on the backside that almost anywhere you draw a line, there will be craters along it!

  39. Chris R

    @38 DrBB: I’m guessing that’s mostly your brain tricking you into seeing those lines. It doesn’t help that the two halves are stitched together pretty blatantly (no fault of the LRO guys, just the way it worked out). You’re probably subconsciously following that line through the center. The other line you mention is very likely just coincidence.

    Not to diminish the “comet breaking up” hypothesis, as that’s far more interesting.

  40. Anchor

    “Ask, and ye shall receive.”

    Okay, folks at LRO. North and South Polar-centered views would be nice too.

    OT: Hey, Phil, have you seen the Kepler Orrery yet?

  41. Chief

    I’ve always liked the explanation by Author James P. Hogan in his Giant’s series of novels on the crust differences in depth.

  42. ChrisP

    @34 Tameron: Now you’ve gone and got me all curious. I wonder if I can do an approximation once I get the spare time…

    (My intended method for finding the time until the moon would be tidally locked would be to use the Earth-moon gravitational Roche limit as an approximation for the radius at which the moon coalesced, and use some combination of conservation of angular momentum and tidal torques to do the estimation. However, I can’t quite figure out how to piece together the appropriate equations)

    Closer to on topic: very nice picture, definitely my personal favorite of the two ‘faces.’ Much less chaotic at first glance, at least as far as contrasts go.

  43. DrBB

    @40. JeffB

    Yup, right, the image stitching is much more obvious in the high res–that’s what was doing it. No less exciting and fascinating an image for the lack of strange linearities. Though ancient alien ruins or a UFO base or two would definitely improve it.

  44. DrBB

    @43: I’ve always liked the explanation by Author James P. Hogan in his Giant’s series of novels on the crust differences in depth.

    Okay, Chief, we’re waiting. Do you wanna share that story with the rest of the class?

  45. Kaleberg

    The first 3D picture of the moon was taken in 1858. They took advantage of libration to make a stereogram. Of course, any newer ones would be way cooler.

  46. owlbear1

    Are there any clearer shots of the poles? Cuz thats where we want to be looking. :)

  47. Why don’t I see The Watcher’s moonbase?! :O :) Selene’s exposed backside on your blog… sir, where is the NSFW?

  48. Don Q

    I think the apparent ‘line’ of extra craters down the middle of the pictures might also be the result of the lighting on the different halves. The shadows on the left half of the ‘photo’ are on the left side of the craters, on the right half, they are on the right side of the crater. Down the middle, there are a lot of split craters with shadows on both sides.

    “Shadows on both sides… How do you explain that!”

    Also, even though the component photos of the composite are taken at comparable moon local times, when the segments are ‘wrapped’ to make the whole picture ’round’ again, the shadows along the edges of the composite are cosine-scaled the same as the craters. Average shadow in the result decreases to zero along the edge of the photo and is max toward the center.

  49. Keir

    I thought the far side of the Moon is more pockmarked because the near side lava plains (maria) are way older, and sort of “fossils.” Thus, if Moon wasn’t in sync with the Earth, it would look more like Mercury, but because it has been in sync with the Earth for billions of years, the side we see hasn’t had so many impacts as the far side, which is unprotected by our close gravitational relationship. The possible near-side lunar impactors have been scooped up by the Earth, and not have hit the side we see, but instead hit the Earth.

  50. DLC

    Phil, I love the pics. I wish I shared your optimism, but I fear that Gene Cernan will be the last man to have stood on the lunar surface.

  51. Messier Tidy Upper

    @^ DLC : So you reckon the Chinese will only be sending women taikonauts there then? ;-)

    Being serious now, I also share that fear. Certainly as far the US goes. A return to the Moon (by humans not just spaceprobes) always seems to be suggested for twenty years in the future – and has been for about the last forty years or so since we left it in the early 1970′s. Same thing as sadly applies to cheap & prevalent use of nuclear fusion and a human landing on Mars. :-(

  52. Messier Tidy Upper

    Great image. Thanks. :-)

    But why does one side have a thick crust and the other thin? No one knows.

    Could the Earth’s gravity have pulled the lunar core slightly towards the Earth-facing side thus creating the imbalance of maria (luna “seas”) & other volcanic activity on that hemisphere and letting the farside crustr get thicker and cooler and more inert?

    Think I might’ve heard / read that explanation for that disparity once.

    EDIT : Just seen that (#9.) mln84 seems to be saying something similiar too.

    I recall discussing the topic of the lunar farside & its differences a few (?) weeks ago here too.

    Of course, there’s always the alternative “pizza” theory that one half crust is pan-fried and thus thin whilst the other is thick or cheesy crust – all covered in green cheese, natch! ;-)

  53. Messier Tidy Upper

    I recall discussing the topic of the lunar farside & its differences a few (?) weeks ago here too.

    See :

    http://blogs.discovermagazine.com/badastronomy/2011/02/22/the-extraordinary-face-of-the-moon/#comment-360777

    Or scroll down to comments #78 & 79 that on the first nearside image post on this which is linked in the opening post here.

    See :

    http://en.wikipedia.org/wiki/Far_side_of_the_Moon#Differences

    For what Wikipedia in its vast collective wisdom says about it too. :-)

    @13. Bob Studer :

    No, because by then, the way things are going, the current “lies” will probably have been replaced by Biblical Truth. Sheesh. 8-/

    I’m more optimistic on that. From my admittedly more distant vantage point it looks like Creationism is in decline and not likely to rise again.

    The US courts have beaten it back several times and they seem to have been so thoroughly discredited that I very much doubt they’ll suceed in forcing their nonsense on future generations – at leats not outside their very narrow and hopefully ever-shrinking circles.

  54. Messier Tidy Upper

    @ ^ “They” there being the Creationists / ID-iot mob not the Courts in case that was unclear! ;-)

    (Correction for bad grammar.)

    @47. Kaleberg : The first 3D picture of the moon was taken in 1858.

    Interesting – thanks. :-)

    But they wouldn’t have had the Lunar Farside on that! ;-)

    @30. DrBB :

    I’d like to endorse Gjeff’s opinion re pepperoni, but where are the anchovies? None, I hope. I hate anchovies.

    WHAT!?!

    See : http://www.youtube.com/watch?v=KNHaiSs7F5E

    I’m with Dr Zoidberg on this – <3 love <3 anchovies! Nothing tastier. :-)

  55. Gary Ansorge

    Hummm, lunar crust thicker on the far side. I guess this is what happens when two massive bodies revolve around a common center of gravity. The denser part gets thrown to the far side of the bodies. Since the moon doesn’t rotate and it cooled more rapidly than earth, the densest part is static, while any such mass distribution on earth would end up throughly mixed as our rotation drags against the lunar tides.

    Eh, sounds logical to me,,,

    Gary 7

  56. Everyone keeps talking about the far side, but I’m yet to see any comics.

  57. Messier Tidy Upper

    An interesting fact I stumbled across tonight that gives an idea of scale – and how lucky Earth is when you consider half the terrestrial (“rocky”) planets in our solar system – Mercury & Venus lack moons altogether :

    *****

    “If we could transport Phobos and Diemos to our own Moon, they would fit comfortably inside the wide crater Copernicus with room enough for two moons of similar size.”
    - Stephen James O’Meara, page 102 “The Demon Sprites of Mars” in Sky & Telescope magazine, June 2001.

    *****

    Copernicus (crater), of course, is on the other near side of our Moon – but that still gives an impressive indication of relative sizes of the three moons of the terrestrial planets – Luna, Phobos & Diemos.

    PS. Straying even further off-topic here, sorry, but does the BA or anyone else know if anyone has searched for Mercury trojans? I know they’ve searched for “Vulcanoid” asteroids inside Mercury’s orbit – but have they looked for trojans around that innermost moon-like world too?

    PPS. Want to confuse others? Print out this photo of lunar farside and one of Mercury and see how many people can pick them apart! ;-)

  58. Messier Tidy Upper

    See :

    http://en.wikipedia.org/wiki/Copernicus_(lunar_crater)

    &

    http://en.wikipedia.org/wiki/Phobos_(moon)

    &

    http://en.wikipedia.org/wiki/Deimos_(moon)

    For comparison purposes and more on those objects noted above. :-)

    PS. Happy 230th anniversary Ouranos* serendipitiously discovered – as a suspected comet – March 13th 1781 by Wilhelm Herschel. :-)

    * That’s how I spell it, its the correct Greek spelling version & I’m sticking to it, durnnit! ;-)

  59. chris j.

    wow, nearly 60 replies, and not one…

    “that’s no moon…”

  60. Jeff P.

    Awesome picture. And it’s stunning that one side is so messed up (Maria) and one side is so clean.

    I’m curious, would nights be a little brighter if the back-side of the moon faced us all the time vs. the frotn? M thought is the lava fields, do a very poor job of reflecting light so maybe up to 20% of the light that could be reflected is sbsorbed or dulled.

  61. William Roeder

    > But how’d the moon get there? How’d it get there?
    > Can you explain that to me? How’d it get there? C’mon. C’mon.
    DC or TLC show ‘what if there was no moon’
    10 million years after the earth formed a collision with a large body ejected the mass that became the moon. That’s why the earth is tilted, has a double core, and why the moon is mostly the same as the Earth’s crust (it has no core.)

  62. Messier Tidy Upper

    @61. chris j. : wow, nearly 60 replies, and not one… “that’s no moon…”

    Hmm .. just for you then, chris :

    That’s no moon .. That’s *our* Moon! ;-)

    Which faras I’ve heard, *does* have a core actually right?

    PS. Where’s Ivan3Man when you need him, eh? ;-)

  63. Messier Tidy Upper

    @ 63. William Roeder : Just in case you don’t already know (& I strongly suspect you do) I think that was referring to this meme :

    http://blogs.discovermagazine.com/badastronomy/2011/02/11/you-cant-explain-bill-oreilly/

    http://blogs.discovermagazine.com/badastronomy/2011/01/31/bill-oreilly-tidal-bore/

    But ardent right-wing Fox fans, needn’t worry – the BA is quoted on the back cover (sort of) :

    http://blogs.discovermagazine.com/badastronomy/2010/05/13/glenn-beck-wait-a-sec-whos-the-idiot-again/

    promoting one of Glenn Beck’s books! ;-)

  64. Messier Tidy Upper

    PS. The above comment is speaking as an Australian who doesn’t get Fox (or any pay-TV) & who is neither left-wing nor right-wing but apolitical hating the idiocies of both sides. A pox (& a-taking of the mickey) on both their houses! ;-)

    I haven’t seen enough of either Bill O’Reilly or Glenn Beck to say whether the BA is justified in his comments or being hyper-partisan against them.

  65. Anchor (#42):

    “Ask, and ye shall receive.”

    Okay, folks at LRO. North and South Polar-centered views would be nice too.

    Or just wait for Google to bring “Google Moon” up to date, like “Google Earth”. Then you can get any view you want. :-)

  66. Maybe it’s like a lot of things in nature. The weaker, lea side is the protected side facing earth. The stronger side, that gets hit most by all the crap flying around out in space, faces out.

  67. Mike

    @entry 34:

    I believe the moon was about 14,000 miles away from the Earth when it finally formed.

  68. Gary Ansorge

    70. Mike

    “I believe the moon was about 14,000 miles away from the Earth when it finally formed.”

    I doubt the moon could have coalesced within Roches Limit, ie, within about 5 planetary diameters(or about 40,000 miles). It would have been just a bunch of debris(but that would make for a pretty ring)

    http://en.wikipedia.org/wiki/Roche_limit

    Gary 7

  69. reidh

    The “fact” that the moon is in anyway constituted in orientation to the earth, suggests that the contrary might be true, this earth moon system being a binary one, I’m sure the center of it is not at the center of the earth’s mass, and therefore they both could be influenced by one another and subsequently seeking a new center of gravity from time to time, hence earthquakes in diverse places and not at regular intervals.

  70. Levi in NY

    Phil, what do you think of the prospects of using the far side of the Moon as a telescope site, since it wouldn’t be subject to radio interference from Earth? Would the benefit of not getting that interference be worth the project of building a telescope there? Are the craters sufficiently smooth and symmetrical that we could convert one into the dish of a radio telescope?

  71. I want Google Moon CraterView.

  72. mike burkhart

    It is important to rember that it was only in the 1960s that we have seen the back side of the moon when a Russian lunar probe sent back a few blury photos.Bill O there are a number of theorys of the Moons origin: 1the Moon was part of the Earth and seperated.2 The Moon formed form matter left over from Earths formation3 the Moon formed somewhere else and was captured by the Earts gravity.4 A large object crashed into Earth thowing debri into orbit that collesed into the Moon.

  73. I don’t see the alien bases. Is this evidence of a cover-up? ;)

  74. DrBB

    @56 “<3 love <3 anchovies! Nothing tastier."

    Guess we'll have to agree to set up our personal lunar bases in different zones then. Me for the highlands around Mare Imbrium. Nice view from up there and the anchovie density is said to be quite low.

    Adding: appalled as I am to find myself in disagreement with a guy whose moniker refers to my favorite amateur-observational objects and an Aussie to boot. It’s like those Greek tragedies. A sad fate dictates that such an essential and irreconcilable difference must eternally divide those who might otherwise be friends.

  75. mike burkhart

    Oh I forgot the ridiculous theroy made by two Russian scientists and beleved by many UFO lovers : The Moon is Giant spacecraft that brought life to Earth from some other planet. There is no evidence to support this. In fact it kind of sounds like a Star Trek episode about the asteroid that was a spacecraft . It was called : For the world is hallow and I have touched the sky.

  76. Chris

    I always thought maybe the centripetal force would cause the far side to be denser, what with everything being pushed the the outer edge.. like a water balloon spinning on a string

  77. Dave

    I have often wondered why the craters on the Moon seem to be circular. It means that they all struck the surface vertically, which means they must have arrived from all different directions. This then means that the craters facing the Earth, could not have formed, because the Earth would have shielded the Moon, if it was at that time tidally locked. The Earth and Moon did not collide with a mass of asteroids, as craters would be oval over most of the surface.

  78. David Snyder

    I can tell you why one side is thin crusted, and I can tell you much more. I study the Moons surface reversed and overlaid over the Earths surface, everyday for the past 2 1/2 years. There is so much obvious evidence and actual proof that Mare Orientale has impacted the Earth several times at least. Every single continent on this Earth has a print from Mare Orientale, some have more than one print. It is the most suppressed subject in science. This is known by many scientist I’m sure. You ask why would this be suppressed, well here is one reason. How would it look if everything that scientist told us about the creation of mountains and everything other geologic structure on Earth, was suddenly shown to be wrong. Well the Moon impacting the Earth shows just that, that they were wrong about many things, and they don’t want to show that. All anybody has to do is use Google Earth, it has a function that allows you to overlay an image over the Earth, and adjust it any way you want. So take an image of Mare Orientale and use a photo editor to flip it horizontally and put it over the Earth.

  79. David Snyder

    Mare Orientale will fit in the center of South America, in the East of Australia, near Mongolia in China, that area of the New Madrid Seismic Zone is a print of the Mare Orientale. Greece is an impact by this crater, and so is Europe. You don’t have to believe me, just look for yourself. It is very easy to do, and just as easy too see. I have some videos on youtube, that will point you in the right direction. Just search Moon Impacts. Username lowpricedpaint. It’s a whole new area of discovery, for most of us anyway.

  80. David Snyder

    By the way, this is not the only crater resulting from an impact with the Earth. Mare Australe is another, as well as Tycho, Jackson, and of course the side we see today, this is the most recent impact. If you look at Mare Orientale, you will see that it used to be dark as well, but seems to have been covered by the debris from the most recent impact, and I think that this is the case with all of the large impacts. Today I was able to confirm that Mare Australe fits, for sure, in the curve of Southern Australia. Why do you think they call it Mare Australe. Australia is truly the land down under, as it was covered by just about every other continent, as the Super Continent. You can clearly see three different impacts, from three different areas of the Moon, in Australia. Mare Australe, Tycho, and Mare Orientale. These same prints can also be seen in other continents in the same pattern, showing us how the super continent was arranged at the time of these impacts. I challenge anyone who would like say I am wrong. I am 100% correct about this, I am! Just Look!

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