Since we’re doing lots of odd things to the earth lately, can we put the moon on it? Very gently, and at rest in the Pacific Ocean. besides floods and crazy tides and all, what happens? would the moon sit there? would it roll around and flatten us all? would gravity be noticibly different on earth near the moon, and could someone stand on the “side” of the moon without falling? what other strange things would happen that will make us think “yeah that would be cool”? and: if the moon isn’t massive enough for crazy anomolies, then say it were made of solid gold. then what?
[WAG]
One problem would be the amount of light blocked out on the Pacific. Probably a lot of fish would die. Though again, this could also mean that a lot of lower-swimming fish that are used to the absence of light would start swimming higher.
I suspect that the atmosphere would be drawn higher off the ground by the moon’s gravity, but of course a lot of it would be being displaced as well. But the likelihood would be that the average thickness of air in the world would either shrink or grow by some amount.
I have no idea what the presence of the moon would do to the Earth’s magnetic poles.
If the Earth and the Moon weren’t bonded, I’m not sure that they would be able to stay together. Humans are kept in place on the surface partly through being so small. But I fear that the moon, even if it didn’t take off when trying to spin with the Earth, would at least roll. And if the moon and earth are bonded together, then I suspect that the rotation of the Earth would slow down, and we’d have a longer day.
[/WAG]
I suspect that no matter how ‘lightly’ you set it down, the ‘weight’ of the moon at near-to-surface earth gravity would be enough to put HUGE stresses on the continental plates… so you’d get earthquakes, volcanoes, and tsunamis at the very least. Suspect that it might be enough force to actually break through the crust, which would mean all kinds of additional hell would break loose.
“Whoops!”
WAG
The moon would be unable to maintain a spherical shape, and collapse into the Earth, forming a very tall mountain. Earthquakes and volcanos ensue.
I wondered about that, Fear, but the moon would probably be better able to maintain its shape in the formation than Earth would… it’s smaller and has a much thicker solid crust, right?? So what would it be like if the Earth ‘collapses around’ the moon?
And also… there’d definitely be some gravitational swings from this much new mass so close to the earth. Maybe enough to cause a substantial rise in air pressure near the moon, and a corresponding drop around on the other side of the planet. (With high winds in between of course.)
I think what would happen is that once both bodies were static relative to each other, gravity would do it’s job to make one and/or the other tear apart and form together as a mass with the smallest potential kinetic energy: a sphere.
[Even with all it’s wrinkles (mountains, ocean basins, circumference variations), the Earth is remarkably more spherical than the most highly polished billiard cue ball. This demonstrates the even-ing out potential of gravity.]
Now if, remarkably, neither broke apart, the center of mass of the Earth/Moon would shift towards the Moon part, and so too would the direction of “down” to those that weren’t on the “top” of either. Total gravity would increase overall.
Near the junction of the spheres, the oblong nature would probably produce a net lightness, as the Moon would pull you “up” from the Earth. (You wouldn’t feel pulled apart, though. The gravitational forces are summative over all the mass of your body.)
On the Moon, would probably be impossible to stay on its surface near the E/M junction, since the net gravity would pull you towards the center of mass, which would be located in the Earth. It’d probably feel like you were on a very steep surface slanted towards the Earth, not on the surface of a level sphere.
P.S. - The probable respherification would take millennia. But aiding that would be all the rubble colliding together. This would generate lots of heat, as the kinetic enengy would be tranferred to heat, melting things together.
The crust is extremely thin on a planetary stale; it’s less than 0.1% of the radius of the Earth. It would crack like an eggshell.
It’s over 2000 miles in diameter! Even if it did fit into the Pacific somewhere (Hawaii might get in the way a bit!) it’s going to stick up over 2000 miles into space!
And I guess it would displace thousands of cubic miles of seawater, which would raise the world’s sea levels a touch, I expect…
The Earth has a mass of almost a hundred times that of the Moon, which would tend to keep the Earth a sphere, while crushing the Moon. Against those kinds of forces, solid rock would disintegrate.
This is a terrible idea, and I, for one, am against it.
Whom do I write? My Congressman? NASA? MENSA? Fox News? A competent mental health professional?
I’d start with the BBB.
Inner solid iron core.
Outer liquid iron core.
Mantle
Crust
The rotating iron core would now be off center of the Earth’s central mass. There would be a large rotating mass chewing away from its former relatively stable location into the Earth’s mantle between it and the former moon. The Solid iron inner core would shift from the center of the outer core and head towards the moon mass. The inner core would be hurled out violently once it shifted into the rotating current of the outer core, like a boat that hits a fast current in a rapids, after sitting in an eddy.
What exactly does the mass differential have to do with who keeps their shape better, in the short term??
The amount of force that the earth is exerting against the moon would be the same as the amount of force that the moon is exerting against the earth, around the point of contact. (Newton’s third law, dontcha know.) The next question is not about mass, but who can withstand that level of force better on a structural basis.
Now, as I get to this point, it occurs to me that I might have missed one way that size might fit into this… the earth is more fragile than the moon on a RELATIVE basis, because it’s so much bigger and more massive… But if the forces are enough to crush rock, they’d crush rock wherever they find it.
So - you’re right that there’s nothing that would reshape the earth drastically. But the crust would get totalled over a fairly large area, about as big as half the moon’s size or so.
Man, this is giving me a headache. 
I saw a program on TV recently that stated out that it’s the moon that keeps the Earth orbitally stable, like a gyroscope. Without the moon, the Earth would tumble.
Preposterous. Planets don’t need to have moons. Mercury and Venus come to mind.
Spreading the material of the moon uniformly across earth’s surface would increase the planet’s radius by about 43 kilometers. It might take several million years for this to happen, but gravity will have its way with things.
I’ve heard this before as well. IIRC, the “tumbling” is more subtle. More like an increase in the precession of the Earth’s rotation, enough to screw up our climate and seasons.
Also, for what its worth, Mercury and Venus are not very good examples. They’re both tidally locked with the Sun.
True enough. However, it’s unlikely that the material of the Moon would spread itself out so neatly. More likely (re the OP), no matter how gently you placed the Moon, the friction involved in the Moon’s collapse and reconstitution with the Earth would be sufficient to make the entire surface of both bodies thoroughly molten as they merged together.
This would not be a hospitable environment for any life on Earth, much less the “fish in the Pacific.” Floods and tides are besides the point–the oceans would be vaporized in the process.
Assuming you could just teleport the Moon onto the surface of the Earth, thus avoiding any friction or other ill effects from the actual movement of the moon:
My WAG, is that the two bodies would be immediately drawn together towards their mutual center of gravity (somewhere within the more-massive Earth). The moon would more or less be drawn into the Earth, both bodies more or less melting from the stresses in the process.
Maybe something like this but with less…you know…“splash”
Naah…Let’s do this the modern way – write an email and send to everyone you know. Someone’s bound to take notice.