Moon was produced by a head-on collision between Earth and a forming planet

January 28, 2016
Photomicrograph of an Apollo 17 sample of lunar highland rock as viewed in cross-polarized transmitted light. Credit: Paul Warren, UCLA

The moon was formed by a violent, head-on collision between the early Earth and a "planetary embryo" called Theia approximately 100 million years after the Earth formed, UCLA geochemists and colleagues report.

Scientists had already known about this high-speed crash, which occurred almost 4.5 billion years ago, but many thought the Earth collided with Theia (pronounced THAY-eh) at an angle of 45 degrees or more—a powerful side-swipe (simulated in the 2012 YouTube video below). New evidence reported Jan. 29 in the journal Science substantially strengthens the case for a head-on assault.

The researchers analyzed seven rocks brought to the Earth from the moon by the Apollo 12, 15 and 17 missions, as well as six volcanic rocks from the Earth's mantle—five from Hawaii and one from Arizona.

The key to reconstructing the giant impact was a chemical signature revealed in the rocks' . (Oxygen makes up 90 percent of rocks' volume and 50 percent of their weight.) More than 99.9 percent of Earth's oxygen is O-16, so called because each atom contains eight protons and eight neutrons. But there also are small quantities of heavier : O-17, which have one extra neutron, and O-18, which have two extra neutrons. Earth, Mars and other planetary bodies in our solar system each has a unique ratio of O-17 to O-16—each one a distinctive "fingerprint."

In 2014, a team of German scientists reported in Science that the moon also has its own unique ratio of oxygen isotopes, different from Earth's. The new research finds that is not the case.

"We don't see any difference between the Earth's and the moon's oxygen isotopes; they're indistinguishable," said Edward Young, lead author of the new study and a UCLA professor of geochemistry and cosmochemistry.

Young's research team used state-of-the-art technology and techniques to make extraordinarily precise and careful measurements, and verified them with UCLA's new mass spectrometer.

This image shows from left Paul Warren, Edward Young and Issaku Kohl. Young is holding a sample of a rock from the moon. Credit: Christelle Snow/UCLA

The fact that oxygen in rocks on the Earth and our moon share chemical signatures was very telling, Young said. Had Earth and Theia collided in a glancing side blow, the vast majority of the moon would have been made mainly of Theia, and the Earth and moon should have different oxygen isotopes. A head-on collision, however, likely would have resulted in similar chemical composition of both Earth and the moon.

"Theia was thoroughly mixed into both the Earth and the moon, and evenly dispersed between them," Young said. "This explains why we don't see a different signature of Theia in the moon versus the Earth."

Theia, which did not survive the collision (except that it now makes up large parts of Earth and the ) was growing and probably would have become a planet if the crash had not occurred, Young said. Young and some other scientists believe the planet was approximately the same size as the Earth; others believe it was smaller, perhaps more similar in size to Mars.

Another interesting question is whether the collision with Theia removed any water that the early Earth may have contained. After the collision—perhaps tens of millions of year later—small asteroids likely hit the Earth, including ones that may have been rich in water, Young said. Collisions of growing bodies occurred very frequently back then, he said, although Mars avoided large collisions.

A head-on collision was initially proposed in 2012 by Matija ?uk, now a research scientist with the SETI Institute, and Sarah Stewart, now a professor at UC Davis; and, separately during the same year by Robin Canup of the Southwest Research Institute.

Explore further: New isotopic evidence supporting moon formation via Earth collision with planet-sized body

More information: Oxygen isotopic evidence for vigorous mixing during the Moon-forming giant impact, Science, DOI: 10.1126/science.aad0525

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baudrunner
Jan 29, 2016
This comment has been removed by a moderator.
torbjorn_b_g_larsson
3.7 / 5 (9) Jan 29, 2016
"Young and some other scientists believe the planet was approximately the same size as the Earth; others believe it was smaller, perhaps more similar in size to Mars."

Moon formation gets even simpler, no size preference, head on collision, volatile delivery afterwards. Though a Mars sized impactor is preferred in accretion models of Earth's core as it would give the 10 % added mass that is the best fit to isotope observations.

My 2c: If the impactor size is huge - Mars or Earth sized - and the added mass is huge - 10 % or 50 %, it gets weird to call one colliding body "Earth". It was a different planet afterwards. Some geologists want to call the pre-collision bodies Tellus and Theia, we should let them.
torbjorn_b_g_larsson
3.8 / 5 (10) Jan 29, 2016
Troll is reported for spamming his anti-factual, anti-science magic, FWIW.
viko_mx
1.9 / 5 (13) Jan 29, 2016
I wonder is it possible the thinking person to believe in such thoughtless idea for the creation of the moon.
Mark Thomas
1 / 5 (3) Jan 29, 2016
"We don't see any difference between the Earth's and the moon's oxygen isotopes; they're indistinguishable."

The identical oxygen isotope ratio is the verifiable scientific result here, so the question is how did this happen? It seems unlikely complete mixing could occur in the very brief time it took the impact to occur, even with a head-on collision. It has been proposed that both impactors had the same oxygen isotope ratios because they formed in the same orbit, possibly near the L4/L5 points of each other. If I recall correctly, simulations of the impact that formed our large moon suggest the impact was off-angle and relatively low velocity. Statistically this makes better sense too, because it is more likely the alignment was not head-on but at least somewhat off angle as a matter of random chance. A head-on impact between similarly sized protoplanetary bodies would probably severely constrain the range of velocities to get complete mixing, but not shatter the impactors.
JongDan
3.4 / 5 (5) Jan 29, 2016
Troll is reported for spamming his anti-factual, anti-science magic, FWIW.

No need to. Let people act retarded if they want to look like retards so much.
Old_C_Code
1 / 5 (6) Jan 29, 2016
"We don't see any difference between the Earth's and the moon's oxygen isotopes; they're indistinguishable."


It makes sense that Earth and Moon have the same origin. Which begs the bigger question; is the Accretion Model of planet formation valid?. Or were moons and planets expelled by the gas giants or the sun early on? Or even crazier (Velikovsky) , get expelled periodically to maintain charge balance? lol (ducking).
Torbjorn_Larsson_OM
4.5 / 5 (8) Jan 29, 2016
@Mark: "It seems unlikely complete mixing could occur in the very brief time it took the impact to occur, even with a head-on collision."

Those are all good points, the Moon and Mars have both basins thought to be from glancing collisions, as well as Vesta IIRC. One way to get apparent complete mixing was presented a few weeks ago. A high velocity collision resulted in a deposition of material where most of the outer Moon shared composition with Earth.

"The models show that the Moon acquires about the final half of its mass from melt condensed in the inner portions of the disc, close to the Earth and just inside the Moon's initial orbit."

The same model predicts that this shared melt is volatile-poor.

"Eventually the disc cools and volatiles condense. But by the time this occurs the Moon's accumulation from this inner disc region has essentially terminated," said Canup."

[tbctd]
Torbjorn_Larsson_OM
4 / 5 (9) Jan 29, 2016
[ctd]

So same isotope ratios outer Moon volatile poor. More impacts will stochastically provide Earth with ~ 1000 times more volatiles according to other work due to the differences in Earth/Moon masses, so volatiles can come from many sources.

@JongDan: I hear you!

@OCC: The accretion model is dominant, and with the recent pebble accretion mechanism simulations can predict all planets naturally. A known alternative would be gravitational collapse, at least for the giants, but those models fit less well.

I've never heard of the ideas you mention, but at a guess they don't work (no 'expel' mechanism, no way to achieve escape velocity, EM effects doesn't get into it). Velikovsky was a mysticist, IIRC.
TheGhostofOtto1923
4 / 5 (8) Jan 29, 2016
wonder is it possible the thinking person to believe in such thoughtless idea for the creation of the moon
Note the callous disregard for evidence. Note the ease with which the godder waves his hand and and makes it disappear.

This is much like the way his god created everything that exists. Is this evidence that viko is created in his gods image?

You bet viko, the collision of a proto-earth with another planet is too messy to be in your book.

But here is yet another example of where your god would not only have had to obliterate evidence, but replace it with totally convincing countrary evidence.

Evidence tampering is a felony. It is a form of deception, is it not?

And so once again you must ask yourself why your god has to DECEIVE you in order to find out how much you TRUST him, when he could have just told the truth the way he promises to do in his book.

Come on. People made up these stories. Isn't that obvious?

And they must've been flaming psychopaths.
Phys1
3.7 / 5 (9) Jan 29, 2016
Presently ignoring:
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baudrunner
Jan 29, 2016
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baudrunner
1.9 / 5 (9) Jan 29, 2016
Presently ignoring:
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..glad you're here! dumbass

If you don't like anybody here, why don't you get the hell out, you egomaniac?
Phys1
3.5 / 5 (8) Jan 29, 2016
@bc
In my judgement you push pseudoscience, see https://sciencex....72681972 . This why I recommend "ignore".
Check your post it contains inconsistencies regarding my presence here.
Old_C_Code
2.3 / 5 (6) Jan 29, 2016
Presently ignoring:
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The close minded incurious like Phys1 shows why Physics is indeed in crisis, they were closer to a unified theory in 1935.

Phys1
3 / 5 (8) Jan 29, 2016
@OCC
It only seems that way to the unskilled. A vast multitude of discoveries since 1935 showed that unification was not at hand. To ignore all of these, like you do, it does not get more closed minded than that.
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julianpenrod
1.6 / 5 (7) Jan 29, 2016
Qualified measurements, or "measurements", yielded a result, whose validity, or "validity", was attested to by the fact it was published, that said the oxygen isotopes on earth and moon were different. Now a qualified measurement, or "measurement", says the isotopes are different! Reminiscent of things like the reports last year that "research" determined that conservatives were happier than liberals, then, a month later, that "research" had determined that liberals were happier than conservatives! And there is the point that no one seems to want to bring up, that a collision with another major planetary object at least could knock the earth out of its orbit, likely into the sun.
bobbysius
3.7 / 5 (3) Jan 29, 2016
You don't need a "head on collision" to explain isotopic differences. If, as is commonly postulated, Theia formed at an L4/L5 point, it would accrete from the same region of the solar accretion disk as Earth and thus be of the same material, with the same isotopic composition. Thus, the Moon's composition would be identical to that of Earth regardless of the relative contributions of each body to it. A head on collision with any decent amount of speed is more likely to have obliterated the Earth and Theia than a 45 degree collision.
Old_C_Code
3 / 5 (6) Jan 29, 2016
It only seems that way to the unskilled. A vast multitude of discoveries since 1935 showed that unification was not at hand.


Another skilled expert at fantasy, ignoring questions he/she should be asking. Like the relationship between Coulomb's law and Newtons law of UG.

It's no wonder these "experts" still can't even explain what happens when two magnets repel one another (See Feynman on magnets, he didn't know why, but I bet Phys1 does).
bschott
2.1 / 5 (7) Jan 29, 2016
It's no wonder these "experts" still can't even explain what happens when two magnets repel one another (See Feynman on magnets, he didn't know why


For anyone of them to actually say it out loud is blasphemy against Mainstream physics religion. You can't "learn" what they have "learned" and then accept a basic physical reality that completely overturns every single thing you have been taught, despite the fact that it is observed reality.

but I bet Phys1 does).


Not a chance. That tool has his head so far up his own ass he could use his toothbrush to comb his hair.
baudrunner
3 / 5 (6) Jan 29, 2016
I don't know how it is that Phys1 officially ignores everyone then continues to respond to the very people he wants to ignore . As I read him, and I am a very perceptive guy, he is a master re-iterator, a class A lickspittle to the mainstream gods of physics, dogmatic to a T. But I doubt that he has an iota of logical reasoning faculties at his disposal. If he did, he would more prepared to parry with the rest of us, engaging in the playful kind of banter that makes sites like this work.

I doubt that you can get him to change his mind about anything. He'd probably shoot sparks out of his ears.
bschott
1.7 / 5 (6) Jan 29, 2016
he is a master re-iterator, a class A lickspittle to the mainstream gods of physics,


Man, I haven't heard the term "lickspittle" in 30 years...nice one, and bang on.
TheGhostofOtto1923
3.7 / 5 (6) Jan 29, 2016
And there is the point that no one seems to want to bring up, that a collision with another major planetary object at least could knock the earth out of its orbit, likely into the sun
Is this what happened because in your mind it 'ought' to have happened that way? Is this the same sort of figuring you employ when you decide that there 'ought' to be a loving god who cares for you personally because after all you're 'worth' it?

Did you do all the calcs for mass, density, relative velocities, trajectory, angle of impact, and etcetc? Just for shits and giggles did you entertain the possibility that the object hit the earth from behind and increased its velocity thereby throwing it into a higher orbit rather than into the sun?

Or do you compose your postings with the same meticulous reasoning you use to fill your toilet?

You know, just bear down and push until something pleasant happens. This 'ought' to be the way it's done yes?
Mark Thomas
2.8 / 5 (5) Jan 29, 2016
Bobbysius, looking at our posts, we are on the same page. Another problem with the head-on collision idea is angular momentum. All the material forming the moon would not only have to get lofted into space from the collision, but it would have to have sufficient angular momentum to go into orbit and form the moon. A perfectly aligned impact would have zero angular momentum by definition.
Solon
2.1 / 5 (9) Jan 29, 2016
Was this a Goldilocks collision then, not too fast, not too slow, just the right angle and area of contact?
It would be more believable that the Moon is artificial and the Gods put it there than the drek the mainstream dream up.
Phys1
4.2 / 5 (5) Jan 29, 2016
@OCC
You guessed right. No-one knows what the EM field is. Already Huygens did not know this.
If you think that you do, you are crazy enough, then enlighten the world and collect the prize.
Otherwise wipe that silly grin of your face.
Rojack
1.8 / 5 (5) Jan 30, 2016
"No-one knows what the EM field is. Already Huygens did not know this.
If you think that you do, you are crazy enough, then enlighten the world and collect the prize."

Phys1

The size and strength of a planet's magnetic field is determined by the size of the planet, the size of its magnetosphere, its distance form the sun, and its speed of rotation. A planet that has no rotation has no magnetic field; See Venus; it rotates about once a year. There is a direct correlation. This is a tough problem to solve because it is so complex. There are too many variables involved and you can't just plug in the numbers. Each planet in space has the potential to develop a strong magnetic field. All it has to do is start rotating. Venus may get its own magnetic field, but it will take a violent act of nature. When you watch this video, you are witnessing the birth of earth's magnetic field. This is out of the box thinking, but if you can do the math, you can claim the prize.
Phys1
2.8 / 5 (5) Jan 30, 2016
@Rojack
Nice explanation, Rojack. Makes sense, to me at least.
Note that Old_Crank demanded an explanation for the magnetic interaction in general, or else. Even if you know your Maxwell equations, your QM, your planetary magnetic fields, unless you fulfil the crank's demand, you are no expert.
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viko_mx
1.7 / 5 (6) Jan 30, 2016
"Moon was produced by a head-on collision between Earth and a forming planet"

In this idea there is no physics. Only wishful thinking.
baudrunner
2.3 / 5 (3) Jan 30, 2016
Nice explanation, Rojack. Makes sense, to me at least.
Hahaha.. you're scraping the bottom of the barrel in your efforts to make friends @Phys1. @Rojack didn't say anything!

This is a tough problem to solve because it is so complex. There are too many variables involved and you can't just plug in the numbers
Nice try. The mechanism behind a planet's magnetic field is pretty clearly understood. Rotation counts, but it's apparent that you don't know why. Earth's magnetic field is strong because it has a liquid conducting iron-nickel core. Mars' field is weak because that core has cooled.
baudrunner
1 / 5 (4) Jan 30, 2016
Some geologists want to call the pre-collision bodies Tellus and Theia, we should let them.
I don't know why they don't just stay with the existing nomenclature. It is thousands of years old. These geologists want credit. I'm not giving it to them.

Pre-Earth/Moon are not called Tellus and Theia. They are called Tiamat and Kingu.
Phys1
4.2 / 5 (5) Jan 30, 2016
"Moon was produced by a head-on collision between Earth and a forming planet"

In this idea there is no physics.

It does not get anymore physical than a head-on collision.
When you say "physical", do you actually mean "religious" and vice versa? That would explain many of your posts.
Only wishful thinking.

Who would wish for a head-on collision of Earth with another body?
Except a vengeful religious nut ?
Phys1
4 / 5 (4) Jan 30, 2016
@br
Congrats, you found out Earth has a liquid metallic nucleus.
At least you are not pushing pseudoscience this time,
only Babylonian myths.
viko_mx
2.6 / 5 (5) Jan 30, 2016
Nice try. The mechanism behind a planet's magnetic field is pretty clearly understood. Rotation counts, but it's apparent that you don't know why. Earth's magnetic field is strong because it has a liquid conducting iron-nickel core. Mars' field is weak because that core has cooled"

So why other rocky planets have no iron-nickel core and magnetic field? Why exactly Earth when in the hypothetical situation, emerged thanks to the theory for the formation of the solar system from the fictional proho cloud, which has expanded with significant speed according to this theory, the heavy chemical elements must be close and sink in the direction to the gravitational center in this cloud.
Shootist
3 / 5 (2) Jan 30, 2016
Those are all good points, the Moon and Mars have both basins thought to be from glancing collisions, as well as Vesta IIRC.


Borealis, or North Pole Basin on Mars? This is still hypothetical, no apparent mantle plume.. (mantle plumes exist for all other large Martian basins, even those with no surface expression).

The lunar SP-Aitken basin is actually two co-incidental basins thought to pre-date the LHB, whether glancing, or not, is still a question under debate.

Rhea (on Vesta) is symmetrical with central uplift, hard to visualize the glancing bit,

Silvia basin was created prior to Rhea and its morphology isn't complete enough to make a decision regarding the bolide's angle of impact.
baudrunner
1 / 5 (3) Jan 30, 2016
At least you are not pushing pseudoscience this time, only Babylonian myths.
Pseudoscience is any science beyond your ken or comprehension or that conflicts with what religious beliefs that you may have.

@Phys1 you fail to understand the broad discipline that defines science. You must accept one of the fundamental definitions of science, " Archaic Knowledge, especially that gained through experience." Quite often I will reach out to archaic knowledge, which we discover through the science of archaeology. A science.
Phys1
4.3 / 5 (6) Jan 30, 2016
@br
Now you are pushing pseudoscience again.
Eikka
3 / 5 (4) Jan 30, 2016
enough influence to temporarily affect the rotation of the Earth enough to keep the heavens in their place for 21 hours


Such gargantuan gravitational force, enough to stop the earth from rotating for a day, would put such a tremendous tidal force on the earth that it would turn pear-shaped and probably result in melting the whole surface from the friction.

Just the act of slowing the earth's rotation to a halt over a 24 hour period would produce an inertial acceleration force of approximately 1.3 m/s^2 sideways on anyone standing on the earth's surface around the Middle East, which would have been noticeable because it's a significant fraction of the earth's gravity. Tall buildings would have tipped over and there would have been massive tsunamis everywhere.

It would have also thrown the moon off its orbit completely.
Eikka
3.4 / 5 (5) Jan 30, 2016
Actually, come to think of it, such a massive body passing through the inner solar system would throw all the planets and the sun off their rockers and slingshot them every which way across the galaxy.
Eikka
2 / 5 (4) Jan 30, 2016
So why other rocky planets have no iron-nickel core and magnetic field?


The magnetic field depends on a dynamo effect, which depends on active plate tectonics. Otherwise the heat flow from the core to the surface isn't fast enough to keep the dynamo going and the currents stop.

the heavy chemical elements must be close and sink in the direction to the gravitational center in this cloud.

You forget the centrifugal force in a rotating cloud of matter. Works a bit like a cyclone vacuum cleaner.

It's harder for the heavy stuff to get into the middle because it carries significant angular momentum. The closer it gets, the faster it starts to spin around, which counteracts the gravitational pull. The lighter elements, especially hydrogen, have an easier time to lose angular momentum through collisions because they don't tend to freeze and clump together so much, so they percolate deeper into the cloud and form the sun.

Phys1
4.2 / 5 (5) Jan 30, 2016
So why other rocky planets have no iron-nickel core and magnetic field? Why exactly Earth ...

Let me guess. I suppose you have all the answers. That leaves ony 1 possibiliy.
The Creator, it was Him, Correct? May His Holy Matrix be Diagonalised!
Eikka
3 / 5 (4) Jan 30, 2016
So why other rocky planets have no iron-nickel core and magnetic field? Why exactly Earth ...

Let me guess. I suppose you have all the answers. That leaves ony 1 possibiliy.
The Creator, it was Him, Correct? May His Holy Matrix be Diagonalised!


Don't bother. Viko is an incorrigible creationist. It's sufficient to just point out the correct theory for the rest of the crowd and leave him to preach in solitude.
Old_C_Code
3.7 / 5 (3) Jan 30, 2016
Rojack says:

A planet that has no rotation has no magnetic field; See Venus; it rotates about once a year. There is a direct correlation.


Mars has no magnetic field and rotates in 24hr 39 minutes. GONG!
Rojack
1 / 5 (3) Jan 31, 2016
Some scientists believe that extraterrestrial impacts produced and maintained earth's internal heat source: its lava. Given that the earth expels more heat than it receives from the sun, is it possible that this impact was the trigger that heated the planet giving it the heat source that cranked up the dynamo system? It is possible whether we understand it or not! In that case, it could still be the event that started earth's magnetic field. Another thing, do you believe that earth and the other planets get their magnetic fields from unique sources or are all the fields created and maintained in a like manner?
Eikka
2.3 / 5 (3) Jan 31, 2016
Mars has no magnetic field and rotates in 24hr 39 minutes. GONG!


The dynamo effect requires convection of hot material between the core and the crust. The coriolis force turns the upwards and downwards flow of material sideways into tube-like vortices in the direction of the planet's rotational axis, and that induces the necessary current to form a magnetic field.

If the planet doesn't have enough heat to have plate tectonics, it doesn't have enough heat for convection plumes and there's no up/down motion of molten matter, which means there's no vortices and little to no magnetic field. Mars is simply too cold to have one.

Venus is hot enough, but it is rotating so slowly that the coriolis force is missing or very weak, and so it gets almost no magnetic field.
Eikka
2.3 / 5 (3) Jan 31, 2016
The coriolis effect is relatively easy to understand.

If you shoot a pistol up at the sky, straight against earth's gravity, the bullet lands back down not on the same spot, but slightly westwards because it lags behind the earth's rotation at the highest point of its arc. It has the same orbital speed as it had on the ground, about 1000 miles per hour, but the circle it needs to travel 1-2 miles up is larger, so the more time it spends up there the further back it will fall.

Same thing happens if there's a blimp 1-2 miles up in the sky stationary relative to the ground, and it drops an object. That object will fall towards east.So if you're shooting at the blimp and the blimp is dropping rocks at you, in order to hit each other the objects going up and down have to form a loop.

That's the coriolis vortex. Cool material sinking down towards the earth's core and hot material rising up towards the surface form spinning loops which are analogous to electric current.
Eikka
1 / 5 (1) Jan 31, 2016
Such vortices of molten material aren't inherently magnetic though, but since they are molten and glowing hot they are highly electrically conductive. That means, if you apply an external magnetic field on such a vortex, it induces an electrical current and that produces an opposing magnetic field in the vortex.

That's how the dynamo starts. There's a separation of charges due to an external magnetic field, such as from the sun, The continued flow of the material in the vortices then transfers energy into the magnetic field and amplify it by increasing the electric current - like a self-exciting generator - which is why it's called the dynamo effect.

Shootist
3 / 5 (2) Jan 31, 2016
@br
Congrats, you found out Earth has a liquid metallic nucleus.
At least you are not pushing pseudoscience this time,
only Babylonian myths.


Earth's core is primarily a solid ball with a radius of about 1220 kilometers (Even if you are "ignoring" me. )
viko_mx
2 / 5 (4) Jan 31, 2016
Only changing magnetic field can induce voltage and currents in conductive environment. if the magnetic field is constant in magnitude and direction over time, it remains conductive medium to move across this field to induce voltage in it.
Old_C_Code
3 / 5 (2) Jan 31, 2016
Note to the chat experts:
A permanent magnet needs no rotation or liquid state to generate a magnetic field.
BartV
1 / 5 (4) Jan 31, 2016
I don't know about you, but when I viewed the video above, it did not seem at all convincing that the moon could form from a collision. And I highly doubt it was done using real physics. I want to see a true-to-physics simulation of how the moon could form from a collision. Just one. Can anyone produce this?

Rojack
1.5 / 5 (2) Jan 31, 2016
Old_C_Code
"Mars has no magnetic field and rotates in 24hr 39 minutes. GONG!"

Good point and thanks for pointing that out! That one point could defeat the notion that it is the external forces that produce the magnetic. However, Mars does not have a fully developed magnetosphere. It has no radiation belts. No radiation belts, no magnetic field!

Rojack
"The size and strength of a planet's magnetic field is determined by the size of the planet, the size of its magnetosphere, its distance form the sun, and its speed of rotation."
AGreatWhopper
2.3 / 5 (9) Jan 31, 2016
baudrunner Jan 29, 2016
This comment has been removed by a moderator.


Thank you! So, how does this senseless cut-and-paste religion get tolerated?

viko_mx2(SFB).1 /5 (11) Jan 29, 2016
I wonder is it possible the thinking person to believe in such thoughtless idea for the creation of the moon.
AGreatWhopper
2.5 / 5 (11) Jan 31, 2016
Presently ignoring:
Benni bschott plasmarevenge cantdrive45 gkam kaiserderden Shootist antigoracle Seeker2 promile swordsman viko_mx DavidW Gigel bluehigh baudrunner solon hyperfuzzy julianpenrod emaalouf theprocessionist wduckss Old_C_Code
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..glad you're here! dumbass

If you don't like anybody here, why don't you get the hell out, you egomaniac?


Not tolerating complete idiots makes one an egomaniac??? Man, I would really like a nice long martial arts sparring session with you. It's obvious you will never take responsibility for your terminal rudeness until someone finally beats it into you.
jljenkins
2 / 5 (8) Jan 31, 2016
According to troll hunter Pandora Hagadakis (remember her?), baudrunner is Steve Lussing of Vancouver, CA.

That's worth considering. You should have a conversation with a random person in a bar there. It's incredible. It's like walking through a bowl of granola. What ain't fruits and nuts is flakes.

EASILY the highest per capita density of tinfoil heads on the planet. Nuking it would raise the world's collective IQ by rather a lot.
Phys1
3.7 / 5 (3) Jan 31, 2016
@Shootist
@br
Congrats, you found out Earth has a liquid metallic nucleus.
At least you are not pushing pseudoscience this time,
only Babylonian myths.


Earth's core is primarily a solid ball with a radius of about 1220 kilometers (Even if you are "ignoring" me. )

Good point. I was only 95% in agreement with current insights. The inner core, 5% of the total core volume, is believed to be solid Fe. The rest is liquid Fe.
___
Presently ignoring:
Benni bschott plasmarevenge cantdrive45 gkam kaiserderden antigoracle Seeker2 promile swordsman viko_mx DavidW BartV bluehigh baudrunner Solon hyperfuzzy julianpenrod emaalouf theprocessionist wduckss Old_C_Code Bigbangcon katesisco jimbraumcos indio007
This list is updated continuously.

Phys1
3.7 / 5 (3) Jan 31, 2016
Some scientists believe that extraterrestrial impacts produced and maintained earth's internal heat source: its lava.

https://en.wikipe...rth#Heat
blazmotronic
2.6 / 5 (5) Feb 01, 2016
The probability of this theory is zero? I thought the moon collided
with the earth? This probability is also zero!
BartV
1 / 5 (3) Feb 01, 2016
I'm glad to see my question down-voted by self-professed scientists who hate to be questioned. Goes to show how political they are.

Phys1
5 / 5 (2) Feb 01, 2016
@BartV
Glad you like it, much obliged.
Phys1
5 / 5 (2) Feb 01, 2016
I don't know about you, but when I viewed the video above, it did not seem at all convincing that the moon could form from a collision. And I highly doubt it was done using real physics. I want to see a true-to-physics simulation of how the moon could form from a collision. Just one. Can anyone produce this?

I think everything you say is wrong without even reading it. Can you say something that I don't think is wrong without even reading it?
Whydening Gyre
5 / 5 (2) Feb 01, 2016
I don't know about you, but when I viewed the video above, it did not seem at all convincing that the moon could form from a collision. And I highly doubt it was done using real physics. I want to see a true-to-physics simulation of how the moon could form from a collision. Just one. Can anyone produce this?

looked pretty straight-forward to me.
a body strikes another, causing a massive discharge of debris - all of which is still gravitationally bound to the emitting body and creating a of "halo" of orbiting matter around it. One piece of that discharge (now orbiting) is massive enough to have it's own "gravity well" to attract some of that debris - building itself an even larger "gravity well". A little time and guess what - a moon...
Otherwise, submit another viable hypothesis...
Mark Thomas
1 / 5 (1) Feb 02, 2016
WG: "looked pretty straight-forward to me."

Fair enough, but the simulation was for an off-center impact, NOT a "head-on collision" as the authors propose. Conservation of angular momentum appears to be an unresolved issue for a "head-on collision."

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