The Moon's origin
August 11, 2017 6:25 PM   Subscribe

What Made the Moon? New Ideas Try to Rescue a Troubled Theory. "Textbooks say that the moon was formed after a Mars-size mass smashed the young Earth. But new evidence has cast doubt on that story, leaving researchers to dream up new ways to get a giant rock into orbit."

"...modern measurements of troctolite 76536, and other rocks from the moon and Mars, have cast doubt on this story. In the past five years, a bombardment of studies has exposed a problem: The canonical giant impact hypothesis rests on assumptions that do not match the evidence. If Theia hit Earth and later formed the moon, the moon should be made of Theia-type material. But the moon does not look like Theia — or like Mars, for that matter. Down to its atoms, it looks almost exactly like Earth."
posted by storybored (27 comments total) 22 users marked this as a favorite
 
Stanley Kubrick.
posted by Ghostride The Whip at 6:27 PM on August 11 [4 favorites]


Faked the moon?
posted by The Gaffer at 7:34 PM on August 11 [1 favorite]




Why the moon?
For the power.
posted by duffell at 7:49 PM on August 11


What power?
posted by dismas at 8:07 PM on August 11 [1 favorite]


Grommit made it, so Wallace would have a place to go for cheese of course.
posted by BigHeartedGuy at 8:18 PM on August 11 [2 favorites]


Hollow, spaceship, ancient aliens, mind control, 9/11, fluoridation, chemtrails, tHE GOVERNMENT!
posted by Literaryhero at 8:29 PM on August 11 [2 favorites]


Hasn't the going theory for ages been that Theia destroyed the entire crust while being destroyed itself, resulting in a mix of Theia and Earth rock in orbit, some of which fell back to earth and some of which condensed into the moon. So the moon should look like the lighter elements of earth, and last I heard it mostly does? They kind of skip lightly over that theory, but certainly I don't remember ever seeing the theory as the moon is made of Theia.
posted by tavella at 8:30 PM on August 11 [14 favorites]


What power?

The power of voodoo!
posted by traveler_ at 8:31 PM on August 11 [5 favorites]


Theory 6, whatever smacked Venus into a slow, anti rotation, also stripped off a moon, and that moon crashed into the great basin, took a rolling takeoff but couldn't make it out of Earth orbit, and paused exactly to become tidally locked as it is. Kind of a momentous but, slow burn, you can see the basin it made about 250 million years ago, I think that is the time frame I saw for the maximum depression in The Great Basin. There is some other stuff out in that area, like gunsight passes, like matter cut away mountains, not to mention how tortured the Earth appears between the Lunar Crater in central Nevada, all the way to what, Bishop and China Lake.
posted by Oyéah at 8:32 PM on August 11


Is this how it's going to be? ...all kinds of FPPs related to the eclipse I'm going to miss?
posted by bonobothegreat at 9:00 PM on August 11 [4 favorites]


The power of voodoo. Who do? You do!

Edit: great minds think alike!
posted by BeeDo at 9:06 PM on August 11


Faked the moon?

It's a little hard to google, but one of my favorite conspiracy theory subcultures out there is Moon denial. Not Moon-landing denial. Moon denial. There are various flavours.
posted by figurant at 9:58 PM on August 11 [6 favorites]


I'm a conspiracy theory conspiracy theorist. I believe that all conspiracy theories were created by the man behind the curtain specifically to bait and trap me.
posted by Literaryhero at 10:30 PM on August 11 [3 favorites]


It's a little hard to google, but one of my favorite conspiracy theory subcultures out there is Moon denial. Not Moon-landing denial. Moon denial. There are various flavours.

"Do an experiment: take a rubber ball and suspend it above a bathtub full of water. Now slowly move the ball closer to the water. Does the level of the water change? Not even slightly. So much for the tides myth."

Holy crap, that's hilarious.
posted by brundlefly at 11:25 PM on August 11 [10 favorites]


"Moon Fuck"
by George Carlin

The way I figure
Fuck the Moon.
posted by Joey Michaels at 1:44 AM on August 12 [1 favorite]


Space egg.
posted by Grangousier at 2:02 AM on August 12 [1 favorite]


"He started with an onion, then he let it dry.
posted by texorama at 2:55 AM on August 12


The lede of this article makes it sound like the Giant Impact Hypothesis was considered settled science, but my understanding was that it was always just that—a hypothesis. There were always problems with it, just fewer problems than other hypotheses had. So it was the leading hypothesis, but not something that scientists were terribly confident about. More research is needed, and all that.
posted by Anticipation Of A New Lover's Arrival, The at 4:17 AM on August 12 [4 favorites]


More research is needed, and all that.

I concur!

I've got the bathtub and a rubbrt ball. You guys bring the booze.
posted by BlueHorse at 6:39 AM on August 12 [2 favorites]


Hasn't the going theory for ages been that Theia destroyed the entire crust while being destroyed itself, resulting in a mix of Theia and Earth rock in orbit, some of which fell back to earth and some of which condensed into the moon.

That's what I thought the theory was, too.

Anyway, I have to ask if this is just some kind of tie-in promotion for The Stone Sky.
posted by tobascodagama at 7:00 AM on August 12 [2 favorites]



The lede of this article makes it sound like the Giant Impact Hypothesis was considered settled science, but my understanding was that it was always just that—a hypothesis. There were always problems with it, just fewer problems than other hypotheses had. So it was the leading hypothesis, but not something that scientists were terribly confident about. More research is needed, and all that.


Well, this is true, but it was so much better than the other models that there was pretty close to consensus that while there were certainly details that needed working on, a version of this was going to be the answer. In graduate school in the '90s, we took it as the answer.

Hasn't the going theory for ages been that Theia destroyed the entire crust while being destroyed itself, resulting in a mix of Theia and Earth rock in orbit, some of which fell back to earth and some of which condensed into the moon.

Basically yes, but in recent years, work on the dynamics involved has turned up issues--for reasonable impact values, you either get a Moon that's pretty much pure Theia or an Earth-Moon system that looks very different from what we have. This article is largely about new work in dynamics that lets you get that thorough mixing.
posted by Four Ds at 10:19 AM on August 12 [3 favorites]


When I was a kid, I recall a theory being taught that the moon was formed at a time when the Earth was a spinning molten mass, and the moon, essentially, tore away from the larger mass, settling into orbit. No intervention by a rogue planetoid.
posted by Thorzdad at 10:25 AM on August 12


Yeah, there's like one mention in a caption of the debris in orbit coming up Theia in computer simulations. So I'm kind of feeling bad-science-articled, because instead of focusing on that and explaining why there's no viable middle point between only-Theia debris and a giant homogeneous glowing cloud, which would be interesting, there's this fake take as if it's a surprise that moon rocks say the moon shares the same material as earth. We've known that for decades.
posted by tavella at 10:28 AM on August 12 [2 favorites]


Well, that's apparently making a comeback, Thorzdad, because that's close to what the "synestia" theory is.
posted by tavella at 10:29 AM on August 12


What you're describing, Thorzdad, is what's usually called the "fission" hypothesis. It was originally rejected because, for all the chemical similarities between the Earth and Moon, the Moon was found to be incredibly volatile-poor. This was explained in the giant impact hypothesis by the impact spraying material out and spreading it around such that volatile materials could escape while more refractory ones were left behind.
posted by Four Ds at 7:29 PM on August 12 [1 favorite]


This sounds like a job for the Moon Patrol!
posted by Cash4Lead at 6:36 AM on August 13


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