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New Moon Formation Model
msheppard writes "This ariticle at Scientific American describes a new computer model describing the formation of the moon. "It is also strikingly similar to the first proposed impact theory 25 years ago, before computer simulations were available.""
Space.com has another version with more graphics.
Except the article refers to a consensus reached 25 years ago, but I believe the actual "collision with a Mars-sized body" consensus came from the Kona, Hawaii meeting in 1984. So that's only 17 years... And basically this model is just an incremental improvement (will a big increment - 20,000 body simulation instead of 3,000) over previous simulations of the process. Still interesting though!
It does lend some
Energy: time to change the picture.
Not a stupid question. The answer is that the gravitational forces exceed the ability of the planet's materials to resist them. Thus the planet's shape assumes that which minimises the gravitationally induced stress, i.e. the sphere. Where the internal gravitational forces are weak, for example within your car or the asteriod Eros, this doesn't happen.
Thank you. Somebody needed to yell at him.
If only JLo would victimize me in this manner...
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And the brethren went away edified.
What have miserable string instruments got to do with this?
If you want to know if your computer model is using a fine enough grid (enough particles) there's a simple way to be sure. Run the simulation with 5000 particles, then 10000, then 20000, etc. Keep doing it until the answer doesn't change much, and you can be pretty sure you have enough particles. Of course, I don't know that they did something like this, but some sort of grid resolution study is pretty standard in any advanced computer simulation. I'd be extremely surprised if they couldn't justify using 20000 particles.
2. Go outside
3. Look at moon
Burn the land and boil the sea, you can't take the sky from me
...that guy could buy Bill Gates, and still have enough left over to purchase quite a few elected officials.
Does he really think that the beam from the average keychain laser pointer could go 238,000+ miles?
What will his next project be? Hooking his laser pointer up to a car battery, putting a telescopic sight on it, and telling us he's augmented his local Neighborhood Watch with its very own homespun missile defense system?
The government should monitor this "project," round up everyone who participates, and unleash them in Iraq or something.
~Philly
If people are wondering if this will work, try this: go to one end of a corridor and try to keep the light fixed on something at the other end. It's almost impossible to keep it stable at 50 meters or so - people would be luck to hit the moon at all.
Just a disclaimer: I know I risk being modded down again for this comment. I'm only posting this comment to clarify the original one.
I had intended to point out that, since the world is habitable now, and since previous civilizations used fossile fuels and pumped the CO2 levels during those civilizations.
That is, assuming ackthpt's stipulations are correct.
One easy way to debunk his theory is to point out the lack of geological evidence.
What's this Submit thingy do?
yeah - understand that much. Read somewhere that the moons composition was very unlike earth's though - ie this material isn't a part of the earth, and couldn't be the remains of anything that hit the earth either.
The easiest way to explain the difference was to claim that the Earth was hit by another object which sloughed off part of the surface, leaving the core largely unchanged. The problem has been getting the timing and mass right: this simulation shows that it had to be about a Mars-sized object at a specific time - any bigger or smaller, or at a different time, and you need multiple collisions to obtain the Earth and moon as we see them today.
-dair (like I say, not an astronomer - just going by what I read in the paper this morning)
It's a space station!
All you need is enough size in the object. A molten interior helps, but I don't think is essential. If you think of the planet as a loose collection of many objects rather than a single solid object, gravity tends to act just as with a liquid or gas, bringing everything to an 'equipotential surface', i.e. a sphere. The spinning of the Earth actually distorts its shape slightly from a sphere. But it's basically a matter of size (and density). As you get down to smaller bodies, in particular the asteroids, they get less and less spherical - you've probably seen pictures of Eros from the NEAR mission: basically a dumb-bell shape, not a sphere at all.
Energy: time to change the picture.
Of course, this all works fine during the day, but what about at night? Even the liberals can't control the rotation of the Earth to prevent nightfall from setting in (only Joshua was able to ask for that particular favor!)
(emphasis mine)
But then our friend goes on to claim:
There is no mention of the "moon" anywhere in literature or historical documents -- anywhere -- before 1950.
Nice try, but you just referenced Joshua 10:12 in the Old Testament (written WAY before 1950, something that EVERYONE will agree on...):
12 Then Joshua spoke to the LORD in the day when the LORD delivered up the Amorites before the sons of Israel, and he said in the sight of Israel, "O sun, stand still at Gibeon, And O moon in the valley of Aijalon."
I'm not a journalist, but I play one on slashdot
For that one time I didn't hit preview...
here
Je t'aime Stéphanie
Dumbass! Those guys from France crashed into it and it didn't pop. In fact, it isn't even spherical; it's round but flat like a cookie -- their ship knocked a 100-mile wide "bite" out of it.
A diamond the size of a planet would crush into roundness...
I am for the complete Trantorization of Earth.
While it isn't likely that present day Earth will encounter another impactor such as may have formed the moon, legitimization of the theory behind this model goes a long way to giving planetary astronomers a better understanding of how planetary systems are formed. If they can't explain how WE got here, then its really difficult to conclude one way or another that similar systems are or are not out there.
For you lazy people...
Basically the article confirms what we all already knew (most of us learning it from the Carl Sagan COSMOS series). They have a model which proves that a solid body mass "escaped from the inner gases of Jupiter" and eventually slammed into the Earth. "The impact caused an extensive spray of material out into space, which gradually coalesced into the Moon."
"And like that
Or pinball.
Everyone but the scientists know the moon wasnt formed by an object impacting Earth. Its just compressed interplanetary curdled milk! DUH!
,
faeryman
Exactly . . . I chose the proof to show that in order to demonstrate something as a unique property (say, the way the moon was formed), you need to not only show that it has the property but also show that it is the only one that has the property (no other formation model is valid).
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I am an expert in electricity. My father held the chair of applied electricity at the state prision.
Astronomers have long agreed that debris from an object impacting Earth formed the moon.
Is this really the case? Last time I sat through astronomy in college they still seemed to make a lot of the "concurrent development" theory. Has that been shown wrong recently?
I'm an Angry Clam. You would be angry too if you were a ball of snot in a shell.
And here I thought it was caused by Ultimate Evil, about 4700 years ago, and it's interaction with the fifth element. (Orange hair-dye?)
Slashdot requires you to wait 30 minutes between publishing articles.
It's been 16 minutes since you hit 'publish'!
A feeling of having made the same mistake before: Deja Foobar
Hang on, I think I've heard this one before... Seems like c.s.s. folk are infesting slashdot these days ;).
Your pizza just the way you ought to have it.
Why don't you submit this as a story to the editors?
Showing that something works is inconclusive . . . showing that everything else doesn't work is better.
Example: Two is the only even prime number. Proof: Two can be divided by one and two. Viola!
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I am an expert in electricity. My father held the chair of applied electricity at the state prision.
Good [un?]intentional space pun!
Slashdot: come for the pedantry, stay for the condescension.
There is no moon...
Je t'aime Stéphanie
Hmmm...
The impact theory is really nice because it explains why the moon seems to have so many fewer minerals and a core that's aparrently rocky instead of metallic.
Still, addicted to eyecandy as I am, I would haved liked to have seen a computer rendered avi or something...
The next Slashdot story will be ready soon, but subscribers can beat the rush and slashdot the links early!
Gravity & spinning
if you divided the surface of the United States into 20,000 longitudinal (sp?, or even a word?) slices of equal width, these "tiny particles" would be in excess of 500ft wide. That's much smaller than if you did it with the whole earth (plus whatever hit it). I dunno, maybe that's all the resolution needed to predict the outcome of celestial events. I'd tend to doubt it. This sounds like a *real* rough and dirty approximation, hardly worth the money it cost to build.
Tom Swiss | the infamous tms | my blog
You cannot wash away blood with blood
If a collision did occur, especially at the incident angle used in the model, would the resulting body have an asymmetric composition? Or would the amount of energy resulting from the impact and the amount of time since the impact permitted a relatively homogeneous composition?
... to the third object? Does it seem odd to anyone else that it is nowhere to be seen?
It amazes me that so many allegedly "educated" people have fallen so quickly and so hard for a fraudulent fabrication of such laughable proportions. The very idea that a gigantic ball of rock happens to orbit our planet, showing itself in neat, four-week cycles -- with the same side facing us all the time -- is ludicrous. Furthermore, it is an insult to common sense and a damnable affront to intellectual honesty and integrity. That people actually believe it is evidence that the liberals have wrested the last vestiges of control of our public school system from decent, God-fearing Americans (as if any further evidence was needed! Daddy's Roommate? God Almighty!)
Documentaries such as Enemy of the State have accurately portrayed the elaborate, byzantine network of surveillance satellites that the liberals have sent into space to spy on law-abiding Americans. Equipped with technology developed by Handgun Control, Inc., these satellites have the ability to detect firearms from hundreds of kilometers up. That's right, neighbors .. the next time you're out in the backyard exercising your Second Amendment rights, the liberals will see it! These satellites are sensitive enough to tell the difference between a Colt .45 and a .38 Special! And when they detect you with a firearm, their computers cross-reference the address to figure out your name, and then an enormous database housed at Berkeley is updated with information about you.
Of course, this all works fine during the day, but what about at night? Even the liberals can't control the rotation of the Earth to prevent nightfall from setting in (only Joshua was able to ask for that particular favor!) That's where the "moon" comes in. Powered by nuclear reactors, the "moon" is nothing more than an enormous balloon, emitting trillions of candlepower of gun-revealing light. Piloted by key members of the liberal community, the "moon" is strategically moved across the country, pointing out those who dare to make use of their God-given rights at night!
Yes, I know this probably sounds paranoid and preposterous, but consider this. Despite what the revisionist historians tell you, there is no mention of the "moon" anywhere in literature or historical documents -- anywhere -- before 1950. That is when it was initially launched. When President Josef Kennedy, at the State of the Union address, proclaimed "We choose to go to the moon", he may as well have said "We choose to go to the weather balloon." The subsequent faking of a "moon" landing on national TV was the first step in a long history of the erosion of our constitutional rights by leftists in this country. No longer can we hide from our government when the sun goes down.
http://129.162.26.201/photolab/moon05.wmv
actually, the idiots who were in charge of the press release on the web stuck some huge 720x480 avi on the web earlier today and made our netowrk grind to a halt. They've since removed that file. (serves them right i guess for not checking with us video guys first about it)
I can assure you that this one is much smaller.
and since i probably shouldn't be posting this(yet), i've decided to be an AC
Interesting theory, however proven false by the fact there there still is and always will be Jews, while subhuman scum like you will be gone and forgotten before long as usual.
He says that he doesn't expect it to work, and even understands why it won't.
He's doing it so that
A ) People will have a good time.
B ) People will be educated by learning about the hurdles involved.
And he's still enthusiastic, knowing it won't work. Maybe his goal isn't to get to name the Great Red Spot of the moon, but just to have a good time.
What's this Submit thingy do?
I confess to ignorance, but I understood the specific gravity of the moon was so different to Earth's, that it could not have been formed from material that originally came from here. Unfortunately, it couldn't be re-ejected material from the impactor either... because that would be half-way to Earth's core and not in a hurry to pop back into space.
Billiards.
Earth-ball in the corner pocket...
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-- your boss
Check out this moron. Paint the moon!
Life is the leading cause of death in America.
White House Selected Vegetables Coffee Mug
at: http://radiofreenation.com
duh
"It is a greater offense to steal men's labor, than their clothes"
2. Drop pants, posterior pointed towrd adversary.
3. Shake Your Booty!
What, me worry?
You are Robert Novak and I claim my five pounds.
I could probably look this up in a 6th grade science book, but why the hell are the planets generally round if such large objects have smashed into them. I wouldn't think there'd be any friction between a planet's surface and space. And if it is from erosion, then how long would such a process take?
Just from general observations, when two things smash into each other they generally don't come off as 2 round pieces.
Like I said, it's a stupid question, but I'm just curious.
The moon is a man-made surveillance ballon used to catch runaway AI's.
Here's the FAQ
Any sufficiently advanced civilization is indistinguishable from Gods.
...Of highly compressed iron, while the moon does not. The moon is almost "all crust", hence overall it's specific gravity is much less.
Black holes are where the Matrix raised SIGFPE
There are ways of getting around the anti-user interaction feature of banjo.
I am interested in what this will do to the acceptance of a viable Space Elevator System... If we already have adequete asteroid orbiting earth, then there is no needfor huge expensive missions out into the asteroid belt to capture on. All that would be needed is to stabalize the orbit so that it is geosynchronous, and then make the elevator..