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Collision With Earth's "Little Sister" Created the Moon
astroengine writes The primordial planet believed to have smashed into baby Earth, creating a cloud of debris that eventually formed into the moon, was chemically a near-match to Earth, a new study shows. The finding, reported in this week's Nature, helps resolve a long-standing puzzle about why Earth and the moon are nearly twins in terms of composition. Computer models show that most of the material that formed the moon would have come from the shattered impactor, a planetary body referred to as Theia, which should have a slightly different isotopic makeup than Earth.
It was only a matter of time before Earth-Two was discovered!
....if both planetary bodies formed in the same area of the accretion disk.
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What about this explanation: a planetoid smashed into early Earth and split Earth into two. The two halves eventually smashed back together, but created the moon in the process. One "half" may have mixed more with the collider than the other due to the angle of impact, creating the slightly different isotopes in the parts of it that became the moon.
Table-ized A.I.
The huge bulk of Theia growing larger in the sky...
Wouldn't Earth and Theia have been both planetoids at that point? One of the new requirements for being a planet is clearing your orbital path. It's pretty clear neither body had done that yet before that point, given the fact they smashed into each other.
Collisions with someone's little sister -- a series of carefully controlled and mutually pleasurable collisions -- often produce new bodies. Why should planet-fuckers be any different?
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So Gaia banged her little sister and made the moon? I assume rule 34 has already been satisfied for this, right?
Serious? Seriousness is well above my pay grade.
So the question I have is, does the fact we have a large moon also the reason we still have our protective magnetic field? I've always kind of assumed the answer is yes without researching it. Wouldn't the relationship of our earth moon magnetic fields interacting each other creates some sort of signature that we can look for? That seems like it could be a potentially noisy event.
I wonder how they did those tests on 'little sister'? I've never even seen her.
It was available through Netflix, but only the DVD-through-the-mail version. Excellent initial video, I think 42 minutes (1 hour minus commercials), which explained this as well as how oxygen came about, and how the moon moves higher in its orbit by 1.5 inches per year, and therefore used to be much closer.
When it was closer, it sloshed the oceans back and forth much more, dragging minerals from the continents into the seas and mixing them.
I find that part the most amazing -- that, without the moon, we might not have become life on this planet. And, if it hadn't receded, we wouldn't have a much more stable environment in which to evolve higher functioning. Like simulating the universe well enough to know past events.
Also I love that the fortune is:
"The number of Unix installations has grown to 10, with more expected." -- The Unix Programmer's Manual, 2nd Edition, June, 1972
-- as I am typing this on an Unbuntu 14.10 x64 installation! The number of Unix installations has certainly grown!
Why should the material composition of Theia have differed all that much from the Proto-Earth? They formed from the same planetary nebula, and at relatively similar distances from the Sun; shouldn't they have been similar in composition? And how can anyone state with any certitude, 4+ billion years later, how much of the merged Earth's crust was from Theia, and how much from the proto-Earth, and whether the lunar material was one, the other, or mostly mixed? It was a long time ago, and the Early Heavy Bombardment period would have stirred things up further. In fact, it's not unlikely that the Early Heavy Bombardment material was long-period debris from the original collision.
If Theia had formed substantially closer, or substantially farther away from the Sun, then the debris from the collision could hardly have remained close enough that the shards would coalesce to form the Moon. The differing orbital velocities would have seen to that.
not really new news
this was a hypothesis pre Apollo
and confirmed from the sample returns
then reconfirmed using computer models of a highly tangential impact
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Little sister wouldn't do that anyway, she's too busy out in the back yard, playing like this
Of course, we only think that our atmosphere is right because we evolved here, in this atmosphere; if the atmosphere had been different, we would have evolved differently, and (had intelligent life developed at all) we'd think that THAT was the right sort of atmosphere.
IIRC earth's atmosphere was different. Our current atmosphere the result of life polluting that environment with oxygen. Causing an environmental catastrophe at the time.
Like Jupiter breaking up an earlier Super Earth, and then the remnants of that larger world becoming the Earth and Moon
Or perhaps Earth and Theia.
I remember another theory explaining the similar composition... Is that during the early age of Earth formation, it was spinning at a very high speed. Some of the mass separated from that mass due to centripetal force becoming a moon, and that's why every year moon is farther away from earth by one centimeter.
Since you gave it a name, we have to feel like we had a twin sister we never met and who died so we could live. Sniff.
If I had a dollar for every time someone came up with a earth moon creation theory, I'd be a millionaire. There is a new paper written almost every month. The truth is, we'll never know. Even if you knew what the earth and moon consisted of all the way through you still wouldn't know exactly how they came to be. So I'm going to add my own theory, the earth and the moon were created when a black hole exploded, The end.
Well that figures. Earth's imouto is to blame for all problems in life.
Or maybe the Moon was here first, and Earth crashed into it. So we're actually on the Moon, and the thing in the sky at night is actually Earth!
Slashdot, fix the reply notifications... You won't get away with it...
At last proof that the world is Muslim .... it banged it's little sister
little sister, don't you.... little sister, don't you.... little sister, don't you me kiss once or twice and then you run.... little sister, don't you do what your big sister done...
So the theory is that there were 2...they collided...and are still 2. They are made of similar stuff too, before and after. I'm sorry, how do we know they impacted again? Oh right...they are slightly different ages...we've mastered that whole dating thing back to 14 billion years. Wait, that doesn't mean they collided...hmmm I'm stumped.
Pictures or it didn't happen...
OK, am I the only one to read that summary and thin "shattered impactor" would be an awesome name for a band?
Lost at C:>. Found at C.