New study proves Moon was created in massive planetary collision

Oct 17, 2012
Massive planetary collision may have zapped key elements from moon
A cross-polarized transmitted-light image of a polished section of Apollo sample 12021.

(Phys.org)—It's a big claim, but Washington University in St. Louis planetary scientist Frédéric Moynier says his group has discovered evidence that the Moon was born in a flaming blaze of glory when a body the size of Mars collided with the early Earth.

The evidence might not seem all that impressive to a nonscientist: a tiny excess of a heavier variant of the element zinc in . But the enrichment probably arose because heavier zinc atoms condensed out of the roiling cloud of vaporized rock created by a faster than lighter zinc atoms, and the remaining vapor escaped before it could condense.

have been looking for this kind of sorting by mass, called isotopic fractionation, since the first brought rocks to Earth in the 1970s, and Moynier, PhD, assistant professor of Earth and Planetary Sciences in Arts & Sciences—together with PhD student, Randal Paniello, and colleague James Day of the Scripps Institution of Oceanography—are the first to find it.

The Moon rocks, geochemists discovered, while otherwise chemically similar to Earth rocks, were woefully short on volatiles (easily evaporated elements). A giant impact explained this depletion, whereas alternative theories for the Moon's origin did not.

But a creation event that allowed volatiles to slip away should also have produced isotopic fractionation. Scientists looked for fractionation but were unable to find it, leaving the impact theory of origin in limbo—neither proved nor disproved—for more than 30 years.

"The magnitude of the fractionation we measured in lunar rocks is 10 times larger than what we see in terrestrial and martian rocks," Moynier says, "so it's an important difference."

The data, published in the Oct. 18, 2012 issue of Nature, provide the first physical evidence for wholesale vaporization event since the discovery of volatile depletion in Moon rocks, Moynier says.

Proof at last: Moon was created in giant smashup
This artist's conception of a planetary smashup whose debris was spotted by NASA's Spitzer Space Telescope three years ago gives an impression of the carnage that would have been wrecked when a similar impact created Earth's Moon. A team at Washington University in St. Louis has uncovered evidence of this impact that scientists have been trying to find for more than 30 years. Credit: Credit: NASA/JPL-Caltech

The Giant Impact Theory

According to the Giant Impact Theory, proposed in its modern form at a conference in 1975, Earth's moon was created in a apocalyptic collision between a planetary body called Theia (in Greek mythology the mother of the moon Selene) and the .

This collision was so powerful it is hard for mere mortals to imagine, but the asteroid that killed the dinosaurs is thought to have been the size of Manhattan, whereas Theia is thought to have been the size of the planet Mars.

The smashup released so much energy it melted and vaporized Theia and much of the proto-Earth's mantle. The Moon then condensed out of the cloud of rock vapor, some of which also re-accreted to the Earth.

This seemingly outlandish idea gained traction because computer simulations showed a giant collision could have created a Earth-Moon system with the right orbital dynamics and because it explained a key characteristic of the Moon rocks.

Once geochemists got Moon rocks into the lab, they quickly realized that the rocks are depleted in what geochemists call "moderately volatile" elements. They are very poor in sodium, potassium, zinc, and lead, says Moynier.

"But if the rocks were depleted in volatiles because they had been vaporized during a giant impact, we should also have seen isotopic fractionation," he says. (Isotopes are variants of an element that have slightly different masses.)

"When a rock is melted and then evaporated, the light isotopes enter the vapor phase faster than the heavy isotopes, so you end up with a vapor enriched in the light isotopes and a solid residue enriched in the heavier isotopes. If you lose the vapor, the residue will be enriched in the heavy isotopes compared to the starting material," explains Moynier.

The trouble was that scientists who looked for isotopic fractionation couldn't find it.

Massive planetary collision may have zapped key elements from moon
Apollo 17 astronaut Jack Schmitt at the lunar rover near Shorty Crater, Taurus-Littrow valley of the moon. Image courtesy of J. Schmitt, the Apollo 17 crew and NASA

Extraordinary claims require extraordinary data

Asked how he felt when he saw the first results, Moynier says, "When you find something that is new and that has important ramifications, you want to be sure you haven't gotten anything wrong."

" I half expected results like those previously obtained for moderately volatile elements, so when we got something so different, we reproduced everything from scratch to make sure there were no mistakes because some of the procedures in the lab could conceivably fractionate the isotopes."

He also worried that fractionation could have occurred through localized processes on the moon, such as fire fountaining.

To make sure the effect was global, the team analyzed 20 samples of lunar rocks, including ones from the Apollo 11, Apollo 12, Apollo 15, and Apollo 17 missions—all of which went to different locations on the Moon—and one lunar meteorite.

To obtain the samples, which are stored in Houston at the Johnson Space Center, Moynier had to convince committee that controls access to them of the scientific merit of his project.

"'What we wanted were the basalts," Moynier says, "because they're the ones that came from inside the Moon and would be more representative of the Moon's composition."

But lunar basalts have different chemical compositions, Moynier says, including a wide range of titanium concentrations. Isotopes can also be fractionating during during the solidification of minerals from a melt. "The effect should be very, very tiny," he says, "but to make sure this wasn't what we were seeing, we analyzed both titanium-rich and titanium-poor basalts, which are at the two extremes of the range of chemical composition on the Moon."

The low and high titanium basalts had the same zinc isotopic ratios.

For comparison, they also analyzed 10 Martian meteorits. A few had been found in Antarctica but the others were from the collections at the Field Museum, the Smithsonian Institution and the Vatican.

Mars, like the Earth, is very rich in volatile elements, Moynier says. "Because there is a decent amount of zinc inside the rocks, we only needed a tiny bit to test for fractionation, and so these samples were easier to get."

What it means

Compared to terrestrial or martian rocks, the lunar rocks Moynier and his team analyzed have much lower concentrations of zinc but are enriched in the heavy isotopes of zinc.

Earth and Mars have isotopic compositions like those of chondritic meteorites, which are thought to represent the original composition of the cloud of gas and dust from which the solar system formed.

The simplest explanation for these differences is that conditions during or after the formation of the Moon led to more extensive volatile loss and isotopic fractionation than was experienced by Earth or Mars.

The isotopic homogeneity of the lunar materials, in turn, suggests that isotopic fractionation resulted from a large-scale process rather than one that operated only locally.

Given these lines of evidence, the most likely large-scale event is wholesale melting during the formation of the Moon. The zinc isotopic data therefore supports the theory that a giant impact gave rise to the Earth-Moon system.

"The work also has implications for the origin of the Earth," Moynier points out, "because the origin of the Moon was a big part of the origin of the Earth."

Without the stabilizing influence of the Moon, the Earth would probably be a very different sort of place. Planetary sciences think the Earth would spin more rapidly, days would be shorter, weather more violent, and climate more chaotic and extreme. In fact it might have been such a harsh world, it would have been unfit for the evolution of our favorite species: us.

Explore further: Rosetta instrument commissioning continues

More information: Zinc isotopic evidence for the origin of the Moon, Nature 490, 376–379 (18 October 2012) doi:10.1038/nature11507 www.nature.com/nature/journal/v490/n7420/full/nature11507.html

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rod_russell_9
3 / 5 (14) Oct 17, 2012
The study does not PROVE anything. It merely offers some evidence to suggest it.
cantdrive85
1.4 / 5 (29) Oct 17, 2012
"This seemingly outlandish idea gained traction because computer simulations showed a giant collision could have created a Earth-Moon system with the right orbital dynamics and because it explained a key characteristic of the Moon rocks."

This "seemingly" outlandish theory has been shown to be "astoundingly" outlandish in light of simulations I have conducted in my crystal ball even by using the "right" (i.e. contrived to agree with the theory) orbital dynamics.
julianpenrod
1.9 / 5 (22) Oct 17, 2012
Among other things, heavier isotopes of zinc are not so much heavier than the lighter ones that the lighter ones would evaporate away before the heavier ones. Note, too, the description that zinc anisotropies on the moon were 10 times that on earth and Mars. But, earth is supposed to have been struck by this supposed other body and the moon spun off! So the earth also should have the same lack of lighter zinc isotopes! And, again, there is the crucial fact that a collision with such a larger,heavier body would have thown the earth intoi a disastrously erratic orbit, maybe even sending it into the sun. And, for that matter, where is this other body? If the earth managed to maintain a stable orbit after the collision, why didn't the other body?
tadchem
4 / 5 (4) Oct 17, 2012
The study supports the theory, but does not prove it. The absence of contrary evidence also supports the theory. The absence of a competing theory that is also consistent with the evidence supports the theory.
A theory is only 'proven' when it is the last one standing after the influx of evidence has slain all the others.
tadchem
4.7 / 5 (15) Oct 17, 2012
Among other things, heavier isotopes of zinc are not so much heavier than the lighter ones that the lighter ones would evaporate away before the heavier ones.

The percent difference between uranium isotopes is even less than those of zinc, but they are routinely separated by mass-dependent diffusion in the gas phase. The mass difference is *enough*.
But, earth is supposed to have been struck by this supposed other body and the moon spun off!

Straw man argument! The moon's mass was vaporized before it recondensed as it made its way past the Roché Limit. It never 'spun off'.
If the earth managed to maintain a stable orbit after the collision, why didn't the other body?

The earth-moon *system* maintained a stable orbit. The collision was relatively non-explosive probably because the impacting object (called Theia) may have been in a horseshoe orbit with the earth. Google it.
PhotonX
3 / 5 (3) Oct 17, 2012
The collision was relatively non-explosive probably because the impacting object (called Theia) may have been in a horseshoe orbit with the earth.
Just as 3753 Cruithne is now? Interesting.
julianpenrod
1.8 / 5 (21) Oct 17, 2012
Separation techniques in the "laboratory" are much more powerful than simple solar wind acting against a gravitational pull many times more powerful. Also, if the lighter isotopes are so vulnerable to separation, how did they gather on the early earth in the first place?
Talking about the moon being spun off wasn't a "straw man" argument, because I wasn't even offering it as an argument! I was just encapsulating the current theory! Supporters of the New World Order "official stories" are getting too infatuated lately with the term "straw man".
A collision doesn't have to be explosive to knock the earth out of orbit. A billiard ball knocks another away without causing an explosion. And there is no way that the other body being in a horseshoe orbit would necessarily guarantee a collision not to be explosive. In fact, if it was in a stable orbit, it wouldn't have hit the earth. Too, among the other questions tadchem failed to answer, where is the body now?
julianpenrod
1.8 / 5 (21) Oct 17, 2012
And why only zinc? Other elements have significant differences in isotope weights! Why are no disparities reported there? And could not differences, if they are real, have been caused by the sites where rocks were collected on the moon having been hit by meteorites or subjected to volcanism?
eachus
4.3 / 5 (11) Oct 17, 2012
Sigh. Big Bad-a-boom! then the vaporized rock condenses. As it condenses, two (hot) big lumps are formed. Volatile metals form an atmosphere around both lumps. Gravity, not temperature will cause fractionation in this atmosphere.

At some point, for each molecular compound, as the system cools both in temperature and entropy, migration from the proto-Moon to the proto-Earth ceases. The signature found here is that the cut-off for heavier zinc isotopes (probably in the form of Zinc Oxide) occurred before the cut-off for the lighter isotopes.

Why wasn't this signature found with other metals? For any explosion there will be a particular cut-off temperature close to the separation from two bodies in one cloud into two separate clouds. Zinc compounds seem to have had the right vaporization points to form the biggest signature. This should also allow those doing the simulations to come up with a better model--in particular of the approach velocity and rotation speeds.
baudrunner
1.5 / 5 (24) Oct 17, 2012
Regardless of your respective beliefs, people, I encourage a reading of the book, "There Were Giants Upon The Earth" by Zecharia Sitchin. It refers in part to the information contained in the ancient Sumerian Clay Tablets on which are published accounts in the cuneiform script about that very collision with the planet Nibiru. Earth was known as Tiamat by the Nibiruans. The accounts are based on communications made to the Sumerians by the "sons of the gods".
Joe_Jones
1 / 5 (8) Oct 17, 2012
Sounds like a plan to me

Privatize-it.tk
Silverhill
4.4 / 5 (7) Oct 17, 2012
@julianpenrod:
earth is supposed to have been struck by this supposed other body and the moon spun off! So the earth also should have the same lack of lighter zinc isotopes!
Not if its greater gravity helped it retain lighter isotopes better.
crucial fact that a collision with such a larger, heavier body would have thrown the earth into a disastrously erratic orbit, maybe even sending it into the sun.
And maybe not. Maybe the impactor happened to fall nearly along Earth's path.
And, for that matter, where is this other body? If the earth managed to maintain a stable orbit after the collision, why didn't the other body?
The other body is still here; we call its gathered remnants the Moon. (After the collision, it was unlikely to be a single body; but gravity worked well even then.)
if the lighter isotopes are so vulnerable to separation, how did they gather on the early earth in the first place?
Greater gravity helped hold them, in the accretion phase.
Frostiken
4.2 / 5 (19) Oct 17, 2012
Why are there so many crackpots on these science sites? Niburu? The New World Order? Do you people have any idea how insane you sound?
Glen_Lincoln
5 / 5 (4) Oct 17, 2012
The article doesn't say how fast they smashed in to one another, but I'm sure it was at more than 500 mph. I wish I could have seen it.
julianpenrod
1.8 / 5 (15) Oct 18, 2012
When the zinc atoms supposedly were thrown into space by the vaporization of the collision, the gravity of earth would not hold the zinc so strongly. Too, Before the moon coalesced, if it coalesced, the zinc atoms, even those that would go into the moon, were held in space close to the earth, so it was the earth's gravity that was responsible for preventing the moon's zinc escaping.
Even in the third body was near the earth's orbit, a collision would have a significant effect. Pushed out of orbit, the earth would respond to the sun's gravity. Even pushed a little further in its general direction pof revolution would still push it out of its orbit, causing it to respond to changes in its path from the sun's gravity.
If the colliding body is the moon, why does the zinc have to be from a collision? It could just as well be that the body formed elsewhere with fewer heavy zinc atoms and been caught by the earth.
And while it was accreting, the earth was less massive
julianpenrod
1.9 / 5 (14) Oct 18, 2012
And while it was accreting, the earth was less massive than today. If it was less massive, how did it hold the light zinc isotopes?
Kedas
1 / 5 (4) Oct 18, 2012
So this is the big bang ;)
visionabler
1 / 5 (1) Oct 18, 2012
Just how much do you suppose the Earth's orbit could be disrupted? Earth spins, and Theia makes a glancing blow in the direction of Earth's spin could be a possible explanation. On the other hand, Earth would have to be hit at a very precise angle and spot in order to seriously dislodge it from orbit.
EBENEZR
3 / 5 (4) Oct 18, 2012
Personally I'm interested to see what the Earth looked like for a while after the collision. I've got this "partially destroyed Death Star" image stuck in my head... Interesting to see evidence backing the idea that the moon was born from, at least in part, the Earth.

Just out of curiosity, does anybody know how slowly a body the size of the moon would have to be moving in order for the Earth to capture it in orbit? After all when you consider the other planets and their moons, ours is pretty massive in comparison.
kevinrtrs
1.8 / 5 (10) Oct 18, 2012
So now they only have to explain the following:
1. Why there's strong indications of water in the deeply buried soil/rocks.
2. Why there's still clear evidence of volcanic activity on the moon today.
3. Why the moon rocks show clear signs of a powerful magnetic field in the past.
4. How does anything accrete at all in a vacuum like space? What exactly is this accretion that's being bandied about so glibly and happily by all and sunder?
Has it ever been observed or demonstrated to happen - anywhere in the whole universe? So far the best lab results can show are small dust bunnies like you'd find in your own household. Gettting anything bigger than that in space will require a miracle.
cantdrive85
2.2 / 5 (13) Oct 18, 2012
So now they only have to explain the following:
1. Why there's strong indications of water in the deeply buried soil/rocks.
2. Why there's still clear evidence of volcanic activity on the moon today.
3. Why the moon rocks show clear signs of a powerful magnetic field in the past.
4. How does anything accrete at all in a vacuum like space? What exactly is this accretion that's being bandied about so glibly and happily by all and sunder?
Has it ever been observed or demonstrated to happen - anywhere in the whole universe? So far the best lab results can show are small dust bunnies like you'd find in your own household. Gettting anything bigger than that in space will require a miracle.


A lot of "miracles" are necessary for many aspects of the "standard theory", the nebular hypothesis is another "miracle" story.
rubberman
3.7 / 5 (9) Oct 18, 2012
"Just out of curiosity, does anybody know how slowly a body the size of the moon would have to be moving in order for the Earth to capture it in orbit? After all when you consider the other planets and their moons, ours is pretty massive in comparison."

I don't know the exact answer, but I can tell you that not only would it have to drift into the system no faster than it's current orbital velocity, but it's approach orientation would have to align it in it's current orbital path....or god put it there with his hand and gave it a nudge, right Kev?

OR, the author of the article is correct as scientific evidence seems to suggest. Personally I can't fathom any other scenario given the variables involved.
EBENEZR
2.3 / 5 (6) Oct 18, 2012
I don't know the exact answer, but I can tell you that not only would it have to drift into the system no faster than it's current orbital velocity, but it's approach orientation would have to align it in it's current orbital path....or god put it there with his hand and gave it a nudge, right Kev?

OR, the author of the article is correct as scientific evidence seems to suggest. Personally I can't fathom any other scenario given the variables involved.


Oh I agree, I'm just curious as to how a "captured" moon could be legitimised. Its formation from existing material seems much more likely.
julianpenrod
2.3 / 5 (9) Oct 18, 2012
With respect to the earth's orbit being disrupted, among other things, rememebr the earth is represented as being in space. That's essentially a "frictionless surface". Imagine a collision between to objects, either of bothof which may be rigid or pliable like clay. On a frictionless surface, these all would move with no problem. If it helps, imagine both also moving and connected by stretched srpings to the same point. Under precise conditions, their centripetal force of movement can equal the force of the springs. Whether spinning or not, whether the objects rebound or stick together, the earth, hit by the other object, would change path, and the spring will start to pull.
julianpenrod
2.7 / 5 (7) Oct 18, 2012
The model of "accretion" has it occurring in several steps, by different forms of interaction.
The earliest part of the process has the sun forming due to gas and dust in a cloud falling to the center by gravity.
Heat and light pressure from the early sun, possible light pressure from other stars and electrical attraction causes particles finer than cigarette smoke to attract.
At the stage of particles in suspension, what can be called "colloids", particles that interact can connect by physical processes of their structures snagging each other. Smaller particles can still be attracted by minor electrical fields and fill in gaps.
From then on up, physical collision generating heat, bonding the objects together, along with gravitation, are credited with building up particles. But, stones in collision show more a tendency to fragment, rather than heat up, which isn't discussed much. Frozen gases and water might cushion impacts and hold particles together.
kevinrtrs
1.9 / 5 (9) Oct 18, 2012
The model of "accretion" has it occurring in several steps, by different forms of interaction.

It's great to have models julian, but somewhere along the line the model needs to meet reality. I'd be very satisfied if someone somewhere can supply us with a real observed occurrence of such accretion in outer space.
Until then, the model remains simple conjecture with zero observational evidence.
IN the case of this particular article there can be any number of reason for the observed facts - none of which need necessarily have anything to do with one heavenly body smashing into another. That part is sheer speculation at this stage since no one can confirm what happened in the past. Not unless you have a time machine handily available?
As for your lovely explanation of accretion - has anyone observed this in space? Please let us know where such observational evidence can be seen.
julianpenrod
2.7 / 5 (7) Oct 18, 2012
As such, no such actual occurrence has been presented as observed. They claim they see disks about other stars with maximum particles ranging from dust to rubble to planets, but the actual process has never been actually described as seen occurring. Submicroscopic particles generally are not observed in action directly, but it's claimed that, in special chamvbers, they have combined to form larger submicri\oscopic particles. Oddly shaped, miniscule pieces of detritus, similar to household dust, can be observed sticking together by physically catching on each other. Meteorites hitting the earth is the closest reported observation of anything similar to accretion by collision. But, in fact, the actual whole process of accretion is space is not reported as having been seen.
baudrunner
2.3 / 5 (6) Oct 18, 2012
Frostiken: We don't sound any insaner than the writer who's saying that the Earth was in a collision millions of years ago with another planetary body when (it was assumed) no-one was around to witness the event. Comments like yours come from people who are too lazy to do the research and to read. I know people who have never read a book in their lives, but aren't above criticizing others for the discoveries they have made based on their readings.
Silverhill
5 / 5 (3) Oct 18, 2012
@julianpenrod:
But, in fact, the actual whole process of accretion is space is not reported as having been seen.
Neither has the whole process of erosion, that has whittled high mountains down to nubs, been seen. The time scale is too great for perception in one human lifetime -- but that, by itself, does not invalidate the model.
TheGhostofOtto1923
3.6 / 5 (20) Oct 19, 2012
But, in fact, the actual whole process of accretion is space is not reported as having been seen.
-But there is an enormous amount of evidence, as opposed to your creation and flood myths, for which there is absolutely NONE, and an enormous amount AGAINST.
It's great to have models julian, but somewhere along the line the model needs to meet reality.
Hi kevin. You should hold your bible myths to the same standard before believing in them don't you think?
I'd be very satisfied if someone somewhere can supply us with a real observed occurrence of such accretion in outer space.
You must know that this is only a natter of time and so you should prepare yourself to admit that you were wrong.

I'm surprised no one posted this vid?
http://www.youtub...a_player

-This may help any but religionists picture the event.
GSwift7
5 / 5 (4) Oct 19, 2012
Separation techniques in the "laboratory" are much more powerful than simple solar wind acting against a gravitational pull many times more powerful. Also, if the lighter isotopes are so vulnerable to separation, how did they gather on the early earth in the first place?


You're not really understanding this, and I haven't seen a cogent explanation yet, so here goes. In a cloud of gas, especially hot gas, held together by gravity, the molecules are constantly bumping into one another. When they bump into eachother momentum is transfered. The difference in mass between isotopes results in the lighter atoms/molecules being imparted with much more speed than the larger ones. This makes them more likely to get enough velocity to escape the cloud. It's all about probability, and it's fairly easy to figure out if you have the percentages. This is basic gas thermodynamics.
GSwift7
4.3 / 5 (6) Oct 19, 2012
As for the transfer of momentum between the two planets in the big collision, it's not an elastic collision. At that size scale, two gravitationally bound objects, whether solid, liquid or gas will all behave as a fluid. The picture at the top is probably a bit deceiving in this regard. It should be something more like two half-full water balloons swinging into each other. They'll stretch, and splash, and mix. There should be some amount of 'explosion' but it's not like smashing two solid rocks into eachother. The planets will want to stick together afterwards. There would probably have been a pair of co-rotating blobs joined together in the middle for a while. There would have been secondary collisions too as some of the parts that splashed off fall back in.

You've gotta remember that solid rock is a fluid under these conditions. Nothing is solid at that pressure and temperature.
avacoder
3.7 / 5 (3) Oct 20, 2012

For all those arguing that the 'imaginary collision' didn't happen because it would have changed the earth's orbit; it probably did. You _assume_ the earth's current orbit is the same as pre-impact. GSwift7 is correct in that at that scale, the two bodies can be viewed as fluid.
Imagine, if you can, that the earth's pre-impact orbit was faster/closer to the sun. If Theia struck in opposition (horseshoe orbit coming in from behind the sun) the resultant orbit of the combined bodies would have been slower and farther from the sun. It's just as plausible that Theia's angle of incidence could have struck a slower orbiting earth farther from the sun and 'knocked' closer in to our present orbit.

That's the problem with creationists; they just can't seem to envision a time when things weren't _exactly_ as they are right now.
IronhorseA
3.7 / 5 (6) Oct 20, 2012
The model of "accretion" has it occurring in several steps, by different forms of interaction.

It's great to have models julian, but somewhere along the line the model needs to meet reality. I'd be very satisfied if someone somewhere can supply us with a real observed occurrence of such accretion in outer space.


I say the same thing about supernatural beings. I want a real observed occurrence (with full background check on the witnesses).
Lurker2358
1 / 5 (4) Oct 20, 2012
The zinc isotopic data therefore supports the theory that a giant impact gave rise to the Earth-Moon system.


I disagree. Objects which collide should have cross-contamination on each other, including mixing up isotopes. The moon having a different isotopic data than the Earth is actually evidence against a collision event.

Example:

Paper towel dipped in red paint, hang it up.

Baseball soaked in blue paint, through it through the paper towel.

red paint and scraps of the paper two will be transferred to the ball, just as blue pain from the ball will be transferred to the paper towel.

The result of all this is simple: the contents of each original object is mixed up.

Now further imagine if the ball and the paper towel vaporized, you'd really have a mix up.

fractionation should have happened with other metals, and in any case, you should still have a light dusting of the lighter isotope on top of the heavier. If water vapor could condense to ice, surely metal vapor can.
Lurker2358
1.8 / 5 (5) Oct 20, 2012
So to me, a different isotopic ratio strongly suggests a totally different origin or creative process from a totally different source material.

Besides all this, what is "special" about the Earth's Moon that you need special pleading to explain it's existence compared to other large moons in the solar system? Take a look at Titan? Will you try to explain that moon as resulting from a similar collision?

Tidally locked?

Nothing special. Mercury is tidally locked, and Venus is nearly so, but with a retrograde rotation.

So obviously a collision even is not needed to explain the Earth's rotation speed, nor the Moon's being tidally locked, Mercury and Venus rotate for more slowly, and they have no satellites. Therefore the scientists argument is totally invalidated by observations of other major planets and their moons, or lack thereof.

How can researchers think outside the box when they can't even think inside the box?
Uneducated
5 / 5 (1) Oct 20, 2012
would the collision explain Earths axial tilt?
Silverhill
5 / 5 (1) Oct 21, 2012
would the collision explain Earths axial tilt?
It might, especially with an impactor as massive as Theia would have been. The collision would have a greater chance of being off-center than not, so a torque would be applied.

Lurker2358, Mercury is not tidally locked; its rotation takes about 59 days, but its revolution takes 88 days.
obama_socks
1.9 / 5 (9) Oct 21, 2012
It's an interesting theory, but their evidence is incomplete. The Moon rocks were collected from a minute fraction of the Moon's surface, considering the grand total size of the Moon, and those collecting the samples did not travel very far from the lander. I don't recall that they collected any samples from the hot, sunny half that we see at night, or from deep craters, so there's some more "evidence" that is missing if, indeed, the Moon was formed after the collision.

Robots sent to the Moon to collect lots of samples from many different locations far and near, and perhaps to analyze the samples 'in situ' where contamination is less likely.
This sounds like something out of Immanuel Velikovsky's "Worlds In Collision".

obama_socks
1.9 / 5 (9) Oct 21, 2012
Earth's axial tilt is only about 23 degrees, compared to Venus at 177 and Uranus at 97 degrees. A collision of such a magnitude might influence such a change in tilt, but then Uranus' axial tilt is much more than Earth's and there's no evidence yet that Uranus was also in a collision. But the chance of a Mars-size planet colliding with two planets within the Solar System is slim.
Torbjorn_Larsson_OM
5 / 5 (3) Oct 21, 2012
@ rod_russel_9, tadchem:

This is a test of a theory, an observation with the theory analogous to "suggestion" (but not really, since it is certifiably predictive).

If science "proved" stuff analogous to mathematics, this would be it.

@cantdrive_85:

The Earth-Moon collision theory is the only one that predicts the observed orbital parameters.

@ baudrunner:

Myths? On a science blog? Not appropriate, and totally useless.

@ julianpenrod:

Fractionation means local loss. We don't know how much volatiles escaped, and we don't need to know it to observe gravitational fractionation.

Meaning you are handwaving. The science remains, however.
Torbjorn_Larsson_OM
4 / 5 (4) Oct 21, 2012
@ kevintrs:

No, "they" don't have to predict in order to have performed a successful testing of earlier theory. Especially these "they", the authors of a single paper.

And none of your points concern Earth-Moon impactor theory. If you weren't trolling, I would take time reply since they are interesting observations all by themselves and we know all of that making it easy to discuss, it's in the literature. But you _are_ trolling.

@ Lurker2358:

What is special with Earth-Moon is in the article, orbital parameters and chemical similarity.

But this is all over the system, Pluton-Charon and many asteroid binaries is the same, so it is not _especially_ special. Just not a disk moon like many or most of the giant's moons.

What you call "special" most people call differing constraints. Nothing special, or in this case even rare, about it.

@obama_socks:

When the planets accreted the chance for collision was not slim at all, that is how accretion happened in the first place.
obama_socks
1.9 / 5 (9) Oct 22, 2012
@obama_socks:
When the planets accreted the chance for collision was not slim at all, that is how accretion happened in the first place.
-Torbjorn

In astronomy, the process of accretion requires the coming together and the cohesion of matter under the influence of gravitation to form larger bodies. In this instance, the larger bodies had already formed although the Earth was most likely not yet complete and still a molten mass. Yet, in that early stage.
It would've had to be large enough to survive such a collision with another body the size of Mars without flying apart, scattering all of its parts and forming something like an asteroid belt.

Early Earth was hit frequently by asteroids, comets, etc. but survived b/c their sizes barely affected the planet. There is a huge difference between 2 planets colliding and the accretion of planetesimals, dust and rocks coming together to form a planet. (contd
obama_socks
1.9 / 5 (9) Oct 22, 2012
(contd)
The solar system was big enough to accommodate all planets and other bodies, which is why I think that a collision should not have occurred unless the other planet was careening into and through the solar system as a rogue from outside of the system. OR, it may have been a planet that broke up and which formed the Asteroid Belt that lies between Mars and Jupiter. My opinion is that the Asteroid Belt is the remains of the Mars-size planet that allegedly collided with Earth and that the moons of Jupiter and of Mars are some of the remnants that were captured by them...but if that were the case, then why wasn't Earth shattered also if the mystery planet is now the Asteroid Belt?

It's been said by some that our Moon's mass was somehow pulled, torn or exploded out of the Pacific Ocean by a supervolcano or two. That's also a theory.
Silverhill
not rated yet Oct 22, 2012
The solar system was big enough to accommodate all planets and other bodies, which is why I think that a collision should not have occurred unless the other planet was careening into and through the solar system as a rogue from outside of the system.
A collision with a wandering extrasolar planet would have been MUCH less likely than an in-system collision while the orbits were still being rearranged by (especially) the giant planets.

why wasn't Earth shattered also if the mystery planet is now the Asteroid Belt?
Especially considering that most of Theia's mass is thought to have merged with Earth, you shouldn't expect great amounts of material to have scattered as far as the Belt. Also, supplying enough energy to cast that much mass into orbits that large would have been difficult.
TheGhostofOtto1923
3.9 / 5 (15) Oct 22, 2012
would the collision explain Earths axial tilt?

So to me, a different isotopic ratio strongly suggests a totally different origin or creative process from a totally different blah

As for the transfer of momentum between the two planets in the big collision, it's not an elastic collision. At that size scale, two gravitationally bound objects, whether solid, liquid or gas will all behave as a blah
Naw I think it probably behaves more like the way that experts have spent much time and money to simulate:
http://www.youtub...a_player

-I suggest you all watch it and save yourselves from just making things up.
TheGhostofOtto1923
3.4 / 5 (18) Oct 22, 2012
The solar system was big enough to accommodate all planets and other bodies...
Because as we all know, solar systems all come in finite sizes for fitting different numbers and types of planets in.
I don't recall that they collected any samples from the hot, sunny half that we see at night
-As opposed to the cold dark side that we don't see? Jesus.

Pussytard is SO uninformed that she thinks the dark side of the moon is actually a real thing. Pussytard, the moon is uniformly illuminated in the same way that the earth is. Please add this to your scrapbook.
It's been said by some that our Moon's mass was somehow pulled, torn or exploded out of the Pacific Ocean by a supervolcano or two. That's also a theory.
Yeah I saw this one in Spaceballs. Remember? 'Suck_suck_suck_suck...' You moron.
URaTard
1 / 5 (9) Oct 26, 2012
Blotto's 'Suck_suck_suck_suck...' comments here indicates his obvious sexual enjoyment of the "gay porn" websites that PussyCateyes gave him due to his constant searching for the RitchieGuy of his dreams, just to try and keep him sexually mollified...at least for awhile. Blotto enjoys fellatio it appears. Thus, his need to type the word "suck" multiple times. That is very abnormal behavior. No wonder he likes the idea of "gay marriage".
Having read all of Pussycateyes' posts, I realized that Pussycateyes is right. Theghostofotto1923 is suffering from Dissociative Identity Disorder, which Pussycateyes, as a mental health nurse. had identified. Although Blotto had Pussycateyes banned from this website, she is on a new name now and has been posting. I know this b/c she has sent me a PM recently attesting to the fact that Theghostofotto1923 is a very mentally disturbed person who uses his many sock puppets to intimidate and to belittle and to lie about individuals with whom he disagrees
EBENEZR
2 / 5 (4) Oct 26, 2012
URaTard

. . .


Completely off topic. Don't derail the thread.

Is it possible that debris may have ever been sub-moons to our moon, but tide force within the moon's tight Hill sphere gradually forced the debris to collide with the moon, causing some of the craters? Sorry if this a completely retarded suggestion.
TheGhostofOtto1923
4 / 5 (20) Oct 26, 2012
Theghostofotto1923 is a very mentally disturbed person who uses his many sock puppets to intimidate and to belittle and to lie about individuals with whom he disagrees
Ahaahaaa look who's talking pussytard you forgot to switch over to your obamasucks suckpuppet before posting. Dimwit.
URaTard
1 / 5 (8) Oct 27, 2012
Nope. I'm not obamasucks. We work for the same company and the same department. I just copied what he had on his computer and decided to use it on mine. I've been watching theghostofotto1923 and all his sickpuppets for years. We all have watched the internet goonie and laughed at everything he says. It's a lot of fun on breaks and lunch.
TheGhostofOtto1923
3.9 / 5 (19) Oct 27, 2012
Nope. I'm not obamasucks. We work for the same company and the same department. I just copied what he had on his computer and decided to use it on mine. I've been watching theghostofotto1923 and all his sickpuppets for years. We all have watched the internet goonie and laughed at everything he says. It's a lot of fun on breaks and lunch.
Well pussytard I do believe this is your most stupidist lie yet.

I suppose you and jewzrule and racistblackguy and the rest of the crack sickpuppet team get together in the lunchroom and have downrate parties, 'cause you all seem to show up together? Just like the blue eagles?

What a gas. Better than doing each others nails I guess. You freaking moron.

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