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Earth May Once Have Had Two Moons

samzenpus posted more than 2 years ago | from the that's-no-moon dept.

Moon 139

AaronW writes "According to a story at space.com, Earth may once have had two moons. The smaller moon, estimated to be 750 miles (1200km) wide and only 4% of the mass of the larger moon, crashed into the far side of the larger moon which caused the features we see today on the moon. The surface of the far side of the moon is quite different than the side facing the earth, having a different composition and a much rougher terrain."

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139 comments

Question for those more knowledgable than I (2)

elrous0 (869638) | more than 2 years ago | (#36975968)

I plead ignorance on the topic, but this explanation strikes me as a little far-fetched considering that it seems more reasonable to me to conclude that the far side of the moon being so different might more reasonably have something to do with the fact that it's permanently facing away from earth. Wouldn't the far side get somewhat more meteor impacts and somewhat more exposure to cosmic radiation, for example? It would seem to me that the earth-facing side would be at least somewhat shielded by earth, compared to the far side--and that over a very long period of time this could make for a difference in geology. For that matter, wouldn't the gravitational field of the earth also have some effect on lunar geology over extremely long periods of time (effecting the two sides somewhat differently), much as the lunar field effects earth's oceans in the very short term?

Perhaps someone more familiar with lunar geology than your humble narrator could explain why these differences are thought to be unrelated to its orientation to earth, and need to be explained instead by a hypothesis as radical as a moon impact.

Re:Question for those more knowledgable than I (2)

arisvega (1414195) | more than 2 years ago | (#36976020)

Hard to say without more quantitative analysis- this moon hasn't always had a 'far side'. There where times where its rotation was not tidaly locked with Earth -i.e. it has not been always showing Earth the same face, this is something that needs time to happen.

Re:Question for those more knowledgable than I (2)

ArsenneLupin (766289) | more than 2 years ago | (#36976112)

it has not been always showing Earth the same face

Yes, that's why, in the olden days, the moon used to be called "full frontal nudity"...

Re:Question for those more knowledgable than I (1)

MightyMartian (840721) | more than 2 years ago | (#36976192)

The Full Moonty?

It is the 2nd Moon that we see. (0)

Anonymous Coward | more than 2 years ago | (#36977316)

EVIDENCE suggests that the remaining celestial body presently orbitting around Planet Earth is actually the 2nd Moon that failed it's half of a mitotic division. The other living half to the Moon became known as the Sun, both were conceived from middle-Earth after the Rock expanded to migrate the Continents to Speciate man into diversity upon the Canopy of Yggdrasil. The Moon in it's present form was itself hallowed into a Space Station by an alien race of supreme beings to cause the increase menstrual cycles of all Earth life to evolve them at expense of lifespan and cultural values. All the so-called Moon rocks exhibitted by NASA are actually foreign impacts and general debris from other orbits and NASA couldn't mine anything from the Moon itself without actual penetrations tools, but they had enough time to play an important game ofminiature golf.

I'm not making this up, not trolling, and my sources are referencable anywhere from Mary Sutherland (http://BurlingtonNews.net) and L A Marzulli (http://lamarzulli.net).

Re:Question for those more knowledgable than I (1)

mr1911 (1942298) | more than 2 years ago | (#36976034)

I'm sure that's it.

Stupid scientists publishing papers always overlook the obvious answers in favor of their "two moons colliding" theories.

Re:Question for those more knowledgable than I (2)

Mindcontrolled (1388007) | more than 2 years ago | (#36976052)

Also pleading ignorance, as I am a biochemist and a moon is a couple of magnitudes away from the scale of things I am used to deal with - from basic physics, though, I don't see how facing/not facing the earth would make a geological difference. Why it should come from another moon impacting there and not from a collision with any old asteroid seems a bit far fetched for me.

Re:Question for those more knowledgable than I (3, Informative)

gcnaddict (841664) | more than 2 years ago | (#36976252)

The explanation given by the paper is that it would've been far more likely for a trojan satellite (one which shares the orbit of our known Moon with the Earth) to have gently crashed into the Moon at a rate of just a few, perhaps one or two, miles per second, which is a collission speed so gentle as to be in absolutely miniscule ranges of probability with an asteroid impact. The net effect of such a slow impact wouldn't be a crater; rather, it would be roughly the same as mashing a clump of dirt on a bigger ball of clay.

As for the far-side bit, the moon wasn't always tidally locked. Tidal locking happens with lots of time.

Re:Question for those more knowledgable than I (1)

Mindcontrolled (1388007) | more than 2 years ago | (#36976276)

I was aware how tidal lock works - we get to look beyond our lab walls and offices every now and then ;) Thanks, though, for the part about the collision speed. Gotta have a look at the paper - that is actually an interesting aspect.

Re:Question for those more knowledgable than I (1)

blair1q (305137) | more than 2 years ago | (#36976652)

1-2 miles per second doesn't make a crater?

that's 4000-8000 miles per hour.

that's certainly crater-worthy.

Re:Question for those more knowledgable than I (2)

tysonedwards (969693) | more than 2 years ago | (#36976384)

The bottom line is that we saw from the Apollo missions and tests conducted on the few Moon rocks that were brought back that the Moon has been tidally locked in it's current orientation for nearly 3.4 billion years (or at least that is what NASA was claiming back in 2005, they may have changed their estimates since). This is assuming that the accretion process and the cooling process to create the Moon did not occur naturally in a tidally locked configuration, which computer models have shown that if an object roughly the size of Mars had collided with the Earth while it was still molten nearly 4.6 billion years ago that the Moon would form in a tidally locked configuration after it accretes.

Considering that current models show that the Moon formed 4.5 billion years ago, the current theory is that for the majority of it's life, the sides that do not directly face the Earth (the edges and the far side as viewed from Earth) are statistically more likely to have been hit than the side facing us, as our gravitational pull would serve to deflect many of those asteroids towards us instead of the near side of the Moon.

The bottom line is that a 750 mile object of 4% the mass of the Moon, colliding at the far side of the Moon (as suggested in this article) would have had a very noticeable effect on the Moon's orbital trajectory around the Earth, providing an eccentric elliptical orbit, make it non-tidally locked, and most importantly would be sending the Moon on a spiral towards us, rather than away from us as we are currently seeing.

Re:Question for those more knowledgable than I (1)

Gerzel (240421) | more than 2 years ago | (#36976712)

The trajectory depends on how hard it hits and at what angle as well as how fast it was moving away to begin with.

Until I see the numbers run in some reasonably good simulations I'm not saying anything.

Re:Question for those more knowledgable than I (1)

vlm (69642) | more than 2 years ago | (#36976070)

From the moon, calculate the percentage of the sky hemisphere covered by the earth. Its really small. Assuming a random distribution of meteors from every direction, the shadow of the earth isn't that impressive.

Another way to look at it, is as a thought experiment, imagine magically all the meteors came from the sun, as a magical point source, rather than randomly everywhere. What percentage of the time does the moon spend in a lunar eclipse? Answer is practically zero.

Note that in low earth orbit, "most of" the hemisphere facing the earth is ... the earth. That's why the cooling system for the ISS is optimized to dump into "earth radiative temperature" whereas the moon landing ships were optimized to dump into mostly empty space. The ISS would not work very well away from low earth orbit.

Re:Question for those more knowledgable than I (4, Insightful)

bberens (965711) | more than 2 years ago | (#36976160)

When you consider the gravitational field rather than line of sight then the "shadow" that Earth casts is really quite large.

Re:Question for those more knowledgable than I (1)

vlm (69642) | more than 2 years ago | (#36976500)

When you consider the gravitational field rather than line of sight then the "shadow" that Earth casts is really quite large.

How so? I agree the gravity field of the earth screws around with "lots" of incoming trajectories. But that still means it hits just about as often.

Lets say, for the sake of argument, that "the system" is contained within a cubical volume of space, a tenth of an A.U. on a side. Something passes thru that cube. No matter how much it curves (more or less) the percentage volume of space represented by the moon is a constant within that cube. So the percentage of impacts is roughly constant.

Re:Question for those more knowledgable than I (1)

dgatwood (11270) | more than 2 years ago | (#36976650)

How so? I agree the gravity field of the earth screws around with "lots" of incoming trajectories. But that still means it hits just about as often.

Because gravity sucks. Earth's gravity is pulling material away from the side facing Earth and towards the side that is away from it. In your model, the number of objects that hit the moon might be the same, but the impacts are now skewed towards objects that would have been farther away in the absence of gravity, and thus, the face of the moon that receives the most impact events isn't the same.

Re:Question for those more knowledgable than I (1)

Kagura (843695) | more than 2 years ago | (#36976782)

How so? I agree the gravity field of the earth screws around with "lots" of incoming trajectories. But that still means it hits just about as often.

Because gravity sucks. Earth's gravity is pulling material away from the side facing Earth and towards the side that is away from it. In your model, the number of objects that hit the moon might be the same, but the impacts are now skewed towards objects that would have been farther away in the absence of gravity, and thus, the face of the moon that receives the most impact events isn't the same.

And objects just a little farther away that wouldn't have impacted anything are now skewed slightly enough towards the earth to reach the moon's orbit and impact the moon. GP was right, earth's gravity doesn't "vacuum clean" or cause a reduced chance of impacts on the moon.

Re:Question for those more knowledgable than I (1)

dgatwood (11270) | more than 2 years ago | (#36977064)

And objects just a little farther away that wouldn't have impacted anything are now skewed slightly enough towards the earth to reach the moon's orbit and impact the far side of the moon.

FTFY.

It is only equal when the moon is roughly 90 degrees from Earth's orbital plane. At that point, the side of the moon facing in the direction of Earth's orbit is going to simply get different impacts.

When the moon is ahead of Earth, objects flying towards the moon hit the back side of the moon anyway.

When the moon is behind Earth, objects flying towards the moon are being actively pulled directly away from it by Earth's gravitational field. Therefore, there will be fewer impacts on that side of the moon.

Re:Question for those more knowledgable than I (1)

blair1q (305137) | more than 2 years ago | (#36976728)

And, anything that is coming past Earth towards the moon is going to be lensed into the moon. Earth's gravity is dangerous.

Maybe that's why there are more big craters on this side.

Re:Question for those more knowledgable than I (1)

rubycodez (864176) | more than 2 years ago | (#36976170)

But the real situation is different. Objects in orbit around the sun go in the same direction. Things get disturbed in outer orbit and get thrown inward, or are in orbits that go far out then back around sun. For things moving the same direction around sun, the Earth forms large shield covering small remote Moon almost half the time , and the other half the time the same face of moon, opposite the earth-facing side, is open to impacts.

Gravity not visible surface (3, Interesting)

perpenso (1613749) | more than 2 years ago | (#36976194)

I don't think you can use the observable earth as an indication of the protection offered. I would expect that the earth's "gravity well" (sorry, a more proper term escapes me at the moment) would be more relevant. That said I am quite suspicious of your overall approach. It seems to be commonly accepted that Jupiter provides the earth with significant protection, now consider the percentage of the sky hemisphere that jupiter occupies.

Re:Gravity not visible surface (1)

newcastlejon (1483695) | more than 2 years ago | (#36978092)

I would expect that the earth's "gravity well" (sorry, a more proper term escapes me at the moment) would be more relevant.

Is it the Hill sphere? I think I remember that being the volume where an object's gravitational attraction is the dominant influence on other objects.

Re:Question for those more knowledgable than I (2)

dgatwood (11270) | more than 2 years ago | (#36976590)

Assuming a random distribution of meteors from every direction, the shadow of the earth isn't that impressive.

First, your initial assumption is begging the question, IMO; the statement that the distribution is random is equivalent to the statement that impacts will be equally distributed, therefore you're saying that impacts will be equally distributed because they are equally distributed.

You would actually expect the majority of meteor impacts in an orbital system to be caused by a fast-moving planet or moon in orbit catching up a slower-moving piece of debris in orbit. Meteor impacts, statistically speaking, tend to come overwhelmingly from the leading side of the planet, and are usually pretty close to falling parallel to the direction of orbit. In the case of moon impacts, that includes both the orbit of the Earth around the sun and the orbit of the moon around the Earth, with the caveat that the latter is largely uninteresting because the speed is so small relative to the former. Thus, there should, in theory, be slightly more impacts on the side of the moon in the direction of its travel, but the difference should be relatively tiny, probably to the point of being undetectable.

Second, it's not the shadow of the planet, but rather the shadow of the gravity well that is significant when it comes to impacts. Earth's gravity well has an effect that extends way beyond its physical surface. So basically, the question becomes one of whether its gravity well is more likely to pull a random hunk of rock into such a position that it would hit the moon or pull it into such a position that it would miss the moon. This question can be answered fairly simply: it will make it less likely to hit the side of the moon that faces Earth and more likely to hit the other side. Earth's gravity pulls random objects towards it. Therefore, if one side of the moon is always facing Earth, it is pulling objects away from that side, and pulling objects towards the opposite side.

This leaves a couple of questions:

1. Is Earth's gravity enough to make up for that disparity?

2. Are the maria disproportionately weighted towards the near side of the moon due to gravity in some way?

If the answer to both of those questions is no, then we can start to consider other curious concepts like a second moon.

Re:Question for those more knowledgable than I (1)

cybergrue (696844) | more than 2 years ago | (#36976156)

I agree. The prevailing theory of why the Moon's sides are so different is because the tidal lock caused the magma flows on the near side. This smoothed things out on the near side while as you stated, the far side was exposed to more meteor impacts. Also, the magma flows are thought to be relatively (in geographic and astronomical terms) recent and possibly ongoing, hence erasing any signs of older impacts under the lava.

What probably happened here is someone decided to model what would happen if the Earth had multiple moons and then realized they would eventually collide.

Re:Question for those more knowledgable than I (1)

Mindcontrolled (1388007) | more than 2 years ago | (#36976212)

Hm, how far into the moon's life did tidal lock set in? Was there enough volcanic activity left for this mechanism to work? With the recent reports on rather young volcanic structures, that might be - but as I said above, I am kinda clueless regarding anything exceeding basic astronomy.

Re:Question for those more knowledgable than I (0)

Anonymous Coward | more than 2 years ago | (#36976176)

It's a good thing you plead ignorance because the moon in fact does rotate.

Re:Question for those more knowledgable than I (1)

elrous0 (869638) | more than 2 years ago | (#36976278)

It's all relative. And I'm sitting on earth, with my relatives.

Re:Question for those more knowledgable than I (1)

alta (1263) | more than 2 years ago | (#36976232)

I just wish they'd figure away to turn the moon around for a while. I'm kinda getting tired of the view, and if there's something different on the other side, i sure as hell want to look at THAT for a while.

Re:Question for those more knowledgable than I (0)

Anonymous Coward | more than 2 years ago | (#36976242)

Yes, I think you've hit it. Two theories that I think have more credence are the following: a planet between Mars and Jupiter exploded and bombarded the "dark side" of the moon with meteors that destroyed the original surface features while preserving the "sunny" side; or the gravity of the Earth caused the moon to expand unevenly, leading to the surface features caused by cracking we see in the night-time sky.

In both cases, scientists won't accept the hypotheses that a planet could explode or that astronomical bodies could expand as much as would need to to cause the moon's mares.

Earth may once *have* had two moons. (2, Insightful)

chaboud (231590) | more than 2 years ago | (#36976008)

Serious guys. You learn read book now. Thanksbye.

Re:Earth may once *have* had two moons. (-1, Flamebait)

Mindcontrolled (1388007) | more than 2 years ago | (#36976080)

Can you bloody grammar nazis take your dictionaries, fold em up until they only consist of sharp edges and shove them up your arse, please? You are doing nothing but lowering the signal to noise ratio on this side - and in the most obnoxious manner. And the Old Ones know, S/N is bad enough already in these parts.

Re:Earth may once *have* had two moons. (0)

Anonymous Coward | more than 2 years ago | (#36976186)

Can you bloody grammar nazis take your dictionaries, fold em up until they only consist of sharp edges and shove them up your arse, please? You are doing nothing but lowering the signal to noise ratio on this side - and in the most obnoxious manner. And the Old Ones know, S/N is bad enough already in these parts.

Irony...

Re:Earth may once *have* had two moons. (1)

RMingin (985478) | more than 2 years ago | (#36976188)

Funny to hear a new guy invoking the Great Old Ones. (This is my second UID, FWIW.) What do you consider G.O.O. status? Anything six digits or less?

Re:Earth may once *have* had two moons. (1)

Mindcontrolled (1388007) | more than 2 years ago | (#36976318)

It's my second, too, after years of lurking before the first. The Old Ones invoked above were purely Lovecraftian, though, and not at all related to UID...

Re:Earth may once *have* had two moons. (1)

subk (551165) | more than 2 years ago | (#36976978)

I took the tinfoil off and got an account in oh..I don't remember. What's the reason for abandoning an account?

Re:Earth may once *have* had two moons. (1)

Mindcontrolled (1388007) | more than 2 years ago | (#36977050)

Didn't check the site for about a year for losing interest. When I came back , I had forgotten my password and had lost my old e-mail account. Being not obsessed with UID, I just got a new account instead of putting up with the hassle of getting the old one back. And, no, the old karma was fine, no need to ask :P

Re:Earth may once *have* had two moons. (0)

Anonymous Coward | more than 2 years ago | (#36976616)

Cthulhu has a UID of -983746983457893457395837985349858739485734895734985374853498.

Crazy right?

Re:Earth may once *have* had two moons. (1)

cowboy76Spain (815442) | more than 2 years ago | (#36977966)

Congratulations! You have inspired me a new sig. As a token of gratitude, I'll use it first here!

Re:Earth may once *have* had two moons. (0)

Anonymous Coward | more than 2 years ago | (#36976312)

That's 'Nazis' - it's a name.

Re:Earth may once *have* had two moons. (1)

Mindcontrolled (1388007) | more than 2 years ago | (#36976372)

That's 'Nazis' - it's a name.

A name I will not honor by capitalization. Also, hook, line, sinker...

Re:Earth may once *have* had two moons. (0)

Anonymous Coward | more than 2 years ago | (#36976376)

Can you bloody grammar nazis take your dictionaries,

Would you bloody grammar nazis

or

Could you bloody grammar nazis

Re:Earth may once *have* had two moons. (1)

Anonymous Coward | more than 2 years ago | (#36976088)

Clearly, the have crashed into the far side of the had, leaving behind a rough grammatical landscape.

Re:Earth may once *have* had two moons. (0)

Anonymous Coward | more than 2 years ago | (#36976130)

no no you are confusing "earth" with "earth may" which an entirely different planet. Earth May is found in the next arm of the milky way. and once upon a time it had 2 moons, but no longer...

Quote from the article (1)

R3d M3rcury (871886) | more than 2 years ago | (#36978162)

A number of explanations have been proposed for the far side's highlands, including one suggesting that gravitational forces were the culprits rather than an impact from Francis Nimmo at the University of California, Santa Cruz, and his colleagues.

Maybe I'm reading this wrong, but are they suggesting that Francis Nimmo and his colleagues hit the moon?

Damn. That Francis Nimmo is so fat...

2 moons? (2, Insightful)

margeman2k3 (1933034) | more than 2 years ago | (#36976010)

That's no moon...

Re:2 moons? (0)

Anonymous Coward | more than 2 years ago | (#36976534)

It looks like we are being pulled in by a tractor beam!

Speak Proper Yoda, Please (0)

wsanders (114993) | more than 2 years ago | (#36976014)

"Earth Two Moons Once May Have Had" ....

Re:Speak Proper Yoda, Please (3, Informative)

YodasEvilTwin (2014446) | more than 2 years ago | (#36976114)

You mean "Two Moons, Earth May Once Have Had" or "Had Two Moons Once, Earth May Have." Yoda often places the predicate (minus the helper verb or all verbs) before the subject -- "Lost a planet, Master Obi-Wan has" -- or otherwise rearranges phrases. He doesn't jumble words around randomly.

Re:Speak Proper Yoda, Please (1)

Mindcontrolled (1388007) | more than 2 years ago | (#36976246)

Obviously, you had to be summoned, YodasEvilTwin... The Master's sentence structure is actually closely related to Latin sentence structure - which actually pretty much allows for near random jumbling. It has a preferred mode, though, which is Yodaesque.

This is why we can't have nice things (1)

ewg (158266) | more than 2 years ago | (#36976016)

Next time, take better care of your natural satellites.

Breaking story... (1)

schmidt349 (690948) | more than 2 years ago | (#36976018)

Details are still sketchy at this point. Reports that the second moon was inhabited by a super-intelligent race using crystals to seal away an ancient evil, and was accessible from Earth via a "Big Whale," could not be substantiated.

Re:Breaking story... (0)

Anonymous Coward | more than 2 years ago | (#36976058)

I loved that game.

Some folks will have trouble accepting this (1)

bogaboga (793279) | more than 2 years ago | (#36976026)

These folks include my Christian, Jewish and Muslim friends, whose religions revolve around the dis-ambiguity that mother earth has always had one moon and not two...otherwise which moon would my friends' holy books be referring to?

Re:Some folks will have trouble accepting this (2)

CannonballHead (842625) | more than 2 years ago | (#36976118)

So a story based on apparently a single study (unproven) that "suggests" that the earth MAY have had (in other words, this *could* be a plausible explanation for why our one moon looks like this). And you already *have* accepted it while criticizing those who won't?

The study hasn't even, as far as I can tell, been reviewed or in some way shown to be plausible, however that works with studies on essentially history.

Re:Some folks will have trouble accepting this (1)

operagost (62405) | more than 2 years ago | (#36976172)

Yes, it's wonderful that the GP poster has summarily dismissed all the world religions as superstition, but still holds enough childish naivete to accept as scientific fact every crackpot theory on the internet.

Re:Some folks will have trouble accepting this (1)

Mindcontrolled (1388007) | more than 2 years ago | (#36976126)

As I do not know many Jews or Muslims, I can only speak for this atheist's Christian friends, who have no problem at all with science. On the large scale, literalist idiots are basically an American problem. Hell, the Vatican has an observatory, with some damn good scientist running it.

Re:Some folks will have trouble accepting this (1)

NevarMore (248971) | more than 2 years ago | (#36976332)

Hell, the Vatican has an observatory, with some damn good scientist running it.

Is the telescope pointed at the playground next door or the window in the nunnery shower?

Re:Some folks will have trouble accepting this (1)

pnewhook (788591) | more than 2 years ago | (#36976152)

The two moons would have been millions of years before any religious texts were written.

Re:Some folks will have trouble accepting this (1)

rubycodez (864176) | more than 2 years ago | (#36976316)

interesting, but they would not see contradiction as this tiny moon became part of The Moon while our earth was still being formed, 10 to 100 million years after whatever caused our present moon to get scooped out of the Earth, long before life appeared. So just a part of creation of our Moon, really.

oh stop it. (2)

mevets (322601) | more than 2 years ago | (#36976374)

You don't need to look to something so esoteric to find missing facts in sacred texts. For example, I don't recall much about micro-organisms in the various bits I've read; however there is a fair amount about various hygienic practices.

Is there really any need to nit-pick at peoples beliefs? Nobody's beliefs are literally right anyways.

Re:Some folks will have trouble accepting this (1)

Captain Spam (66120) | more than 2 years ago | (#36976720)

As longtime watchers of QI know, comedian Rich Hall already has a hard time accepting the entire concept of there being two moons around earth, even without this revelation. He'll be insufferable now. Stephen won't be able to shut him up.

Heh? (0)

Anonymous Coward | more than 2 years ago | (#36976722)

I would put myself in the camp of Christians who would be called evangelical. No problem with this whatsoever.

Except for the Young Earth Creationists, no one would have a problem with this. And they wouldn't have a problem with their once being two moons, but with the timeframes involved.

Re:Some folks will have trouble accepting this (1)

Reapman (740286) | more than 2 years ago | (#36977456)

How so? just curious where a second moon would somehow invalidate their beliefs. Oh wait this is just flamebait to get a religious discussion going and get us completely off topic. My bad!

So (0)

Anonymous Coward | more than 2 years ago | (#36976050)

The earth once had thousands of moons, if the theory of how it coalesced from space dust is correct, right?

At one point, the earth would have been nothing but moons, if you think about it.

At what point does it stop being "rotating cloud of rocky debris", and become "planet, with moooooooons"

In my pants... (0)

Anonymous Coward | more than 2 years ago | (#36976098)

I once had 2 moons in my pants...

A French Nightmare (1)

Anonymous Coward | more than 2 years ago | (#36976128)

"It is entirely plausible for a Trojan moon to have formed in the giant impact, and for it to go unstable after 10 million to 100 million years and leave its imprint on the moon," study coauthor Erik Asphaug, a planetary scientist at the University of California, Santa Cruz, told SPACE.com. Imagine "a ball of Gruyere colliding into a ball of cheddar."

shudder

Second moon (1)

rossdee (243626) | more than 2 years ago | (#36976142)

Did it have a shadow of a jumping mouse on?

There is no Dark Side of the Moon really, matter of fact its all dark.

Already knew this (0)

Anonymous Coward | more than 2 years ago | (#36976148)

Beast wars taught me the other moon was a superweapon that got exploded up.

http://www.youtube.com/watch?v=TQ3flFpD19M&feature=player_detailpage#t=285s

That was no moon... (0)

Anonymous Coward | more than 2 years ago | (#36976178)

...it was a space station.

The Real Far Side of the Moon (1)

dummondwhu (225225) | more than 2 years ago | (#36976224)

It's a known fact that the real far side of the moon is just a Hollywood-caliber set that was created on some government base. Why? Because the real far side of the moon contains a Jetsons-like society of humans who have no concept of a debt ceiling.

Final Fantasy IV (2)

MoldySpore (1280634) | more than 2 years ago | (#36976398)

No. The second Moon was the home to the Lunarians [wikipedia.org] . The Lunarians are a race of beings from a world destroyed which became the asteroid belt, and are identified by a moon-shape crest on their foreheads. They created this artificial moon, resting until a time they believe their kind can co-exist with humans. But the whole second moon thing got screwed up for everyone, because after Cecil whooped Zeromus' ass, the Lunarians decided to throw that moon into gear and get the hell away from us.

Thanks for nothing, Lunarians.

Sadly, it was destroyed (1)

Karl Cocknozzle (514413) | more than 2 years ago | (#36976456)

Sadly, it was destroyed during an accidental "mooning" maneuver the Earth was trying to direct at Venus over some perceived sleight from the previous drunken weekend at the Solar System Club*.

*Membership required.

Re:Sadly, it was destroyed (1)

Cogita (1119237) | more than 2 years ago | (#36976624)

Sadly, it was destroyed during an accidental "mooning" maneuver the Earth was trying to direct at Venus over some perceived sleight from the previous drunken weekend at the Solar System Club*.

*Membership required.

Note: This was unrelated to the events preceding Pluto's expulsion, which was the result of his fraudulent claims to be an only child.

Evidence? (1)

JazzHarper (745403) | more than 2 years ago | (#36976532)

I read the article, but could not find any mention of observations or physical evidence which supports this hypothesis better than, or even as well as, any generally accepted theory. The article only seems to describe a simulation that the authors cooked up. It would seem that such a collision would have some significant residual effects on the orbit of the moon. I could not find any mention of the time period in which this hypothetical collision occurred. Would there be any geological evidence for it on the earth? Perhaps the space.com article is poorly written but, on the face of it, this theory doesn't seem to have anything going for it.

Re:Evidence? (1)

SnarfQuest (469614) | more than 2 years ago | (#36976938)

When parts of the moon crashed into the Earth, it killed all the dinosours. You don't see any dino's do you, which proves it to be true.

The crash of the moons was caused by George W Bush not signing the Kyoto treaty, which created global warming which is caused by man, which caused the cheese moon to crash into the mooncake moon, which is why out moon is now the cheesecake moon. There's only one moon now, which is proof that global warming is caused by man!

Sold it (0)

Anonymous Coward | more than 2 years ago | (#36976554)

We sold it to the people of Kababa
  http://danbern.redacorn.net/lyrics/twomoons.html

Cheese (1)

mswhippingboy (754599) | more than 2 years ago | (#36976852)

I still cling to the "Moon is made of cheese" theory, though the thought of two moons colliding does seem intriguing, especially if one was made of Colby and the other Monterey-Jack.

Pink Floyd had it right man (1)

shoehornjob (1632387) | more than 2 years ago | (#36976874)

I always knew there was something special about the Dark Side of the Moon. "There is no dark side of the moon really. Matter of fact it's all dark." Queue the "get off my lawn dirty hippie" remarks.

Nope... (0)

Anonymous Coward | more than 2 years ago | (#36976958)

Nope...

And God made two great lights; the greater light to rule the day, and the lesser light to rule the night: he made the stars also.

I know this for a fact (1)

PopeRatzo (965947) | more than 2 years ago | (#36977082)

Earth May Once Have Had Two Moons

And one of them had the face...of Jackie Gleason!

I've seen pictures.

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