the moon slowing down

[AL_DA_GREAT]

What would happen to Earth if the moon slowed in its orbit?

 

[Ziggy Stardust]

Well, we could stop worrying about Global Warming, that's for sure.

 

[GoodGame]

Centripetal acceleration stops fighting the force of gravity?

 

[Perfection]

What do you mean, if? Where've you been for the past 4.5 billion years?

Anyways, the day gets longer, tides get weaker, eclipses get shorter and less frequent.

 

[Valka D'Ur]

Isaac Asimov wrote an essay about this subject. Sorry, I don't recall offhand which collection it's from (The Sun Shines Bright comes to mind, though). It's quite riveting.

 

[El_Machinae]

We'd basically have to refigure the Laws of Physics, which physicists would enjoy, but I would not

 

[LulThyme]

We'd basically have to refigure the Laws of Physics, which physicists would enjoy, but I would not

Nonsense. Perf already mentioned that the moon's revolution time is increasing because of tidal forces.

 

[Imperialmajesty]

Lets not forget that the Moon is moving away from the earth... About 3 centimeters a year.

Anyway, what type of slow down are we talking about? Good news is that we would see the dark side of the moon on the earth.

Anyway... theoretically, if the moon "slowed down", the moon would begin to come closer and closer to the earth until reaching the Roche limit. Then the moon will break up and we will all die.

 

[cardgame]

Lets not forget that the Moon is moving away from the earth... About 3 centimeters a year.

I just watched a History Channel show on this, it's 3.5 or 3.8 per year. If it hit Earth, Life as we know it is gone. The human race is, for sure.

Where've you been for the past 4.5 billion years? It's doing the opposite!

Anyways, the day gets shorter, tides get much stronger, eclipses get longer and more frequent.

Also, the Earth's tilt would vary between 0 and 90 degrees instead of staying nearly fixed at 23.5 or whatever it's currently at.

FIXED!

 

[Perfection]

Lets not forget that the Moon is moving away from the earth... About 3 centimeters a year.

Anyway, what type of slow down are we talking about? Good news is that we would see the dark side of the moon on the earth.

Anyway... theoretically, if the moon "slowed down", the moon would begin to come closer and closer to the earth until reaching the Roche limit. Then the moon will break up and we will all die.

I just watched a History Channel show on this, it's 3.5 or 3.8 per year. If it hit Earth, Life as we know it is gone. The human race is, for sure.



Also, the Earth's tilt would vary between 0 and 90 degrees instead of staying nearly fixed at 23.5 or whatever it's currently at.

FIXED!

WRONG!

Physics 101.

The slower the object orbits around something the FARTHER out it is. Mercury is faster then Venus which is faster then Earth which is faster then Mars... etc. As the moon slows down it recesses out, it won't come crashing to Earth but will instead go farther away.

I'm not sure what the impacts on tilt will be, though.

 

[Camikaze]

Doesn't that just mean that the closer an object's orbit is to Earth, the faster it must go in order to maintain its orbit, meaning that if it slows down, it will not be able to maintain its orbit, and will come crashing down to Earth. It will consequently gain speed, but it will initially have to slow down in order to fall out of its orbit. Isn't that the principle behind orbital decay?

 

[peter grimes]

I thought orbital decay had more to do with atmospheric drag... in other words, not applicable to objects as far out as the Moon.

 

[ParadigmShifter]

Someone said we will eventually be able to see more of the dark side of the moon, that's incorrect. In fact, the moon is affecting earth's spin so eventually earth will be tidally locked to the moon and we will only be able to see the moon from 1 hemisphere.

 

[cardgame]

WRONG!

Physics 101.

The slower the object orbits around something the FARTHER out it is. Mercury is faster then Venus which is faster then Earth which is faster then Mars... etc. As the moon slows down it recesses out, it won't come crashing to Earth but will instead go farther away.

You're overthinking it, bro.

Doesn't that just mean that the closer an object's orbit is to Earth, the faster it must go in order to maintain its orbit, meaning that if it slows down, it will not be able to maintain its orbit, and will come crashing down to Earth. It will consequently gain speed, but it will initially have to slow down in order to fall out of its orbit. Isn't that the principle behind orbital decay?

 

[Chieftess]

Anyway... theoretically, if the moon "slowed down", the moon would begin to come closer and closer to the earth until reaching the Roche limit. Then the moon will break up and we will all die.

Speaking of which, since the moon is 1/4th the size of the Earth, how does the Roche limit handle objects of comparible size? Wouldn't the Earth also feel some effects since it would have a (probably very short) Roche Limit? The moon's Roche limit is something like 5900 miles (the moon is 2100 miles wide, not much time for the Roche limit to take effect if the moon were on a steeper trajectory...).

 

[History_Buff]

Also, the Earth's tilt would vary between 0 and 90 degrees instead of staying nearly fixed at 23.5 or whatever it's currently at.

No it wouldn't, and such a suggestion doesn't make any sense. The moon isn't even in the equatorial plane, it orbits near the ecliptic.

 

[cardgame]

No it wouldn't, and such a suggestion doesn't make any sense. The moon isn't even in the equatorial plane, it orbits near the ecliptic.

I'm not talking about planes and orbits, I'm talking about gravity. And possibly magnetics.

 

[Perfection]

Doesn't that just mean that the closer an object's orbit is to Earth, the faster it must go in order to maintain its orbit, meaning that if it slows down, it will not be able to maintain its orbit, and will come crashing down to Earth. It will consequently gain speed, but it will initially have to slow down in order to fall out of its orbit. Isn't that the principle behind orbital decay?

Sure, a force acting against the moon's motion would slow it down briefly and then result in faster motion. I'm getting the impression that the OP said this is a more permanent slowing, rather then a temporary slowing followed by increased speed.

I thought orbital decay had more to do with atmospheric drag... in other words, not applicable to objects as far out as the Moon.

Well, there are forces that can cause a moon to spiral inward besides atmospheric drag. A notable example is Neptune's moon Triton which has retrograde orbit that makes it move closer to Triton rather then farther away.

You're overthinking it, bro.

I'm not over thinking, you're under thinking. Regardless of the OP's intent (forced short term slowing, versus gradually slowing over long periods) you're still wrong. The moon has been generally slowing down for the past 4.5 billion years, not doing the exact opposite.

 

[cardgame]

Sure, a force acting against the moon's motion would slow it down briefly and then result in faster motion. I'm getting the impression that the OP said this is a more permanent slowing, rather then a temporary slowing followed by increased speed.

Well, there are forces that can cause a moon to spiral inward besides atmospheric drag. A notable example is Neptune's moon Triton which has retrograde orbit that makes it move closer to Triton rather then farther away.

I'm not over thinking, you're under thinking. Regardless of the OP's intent (forced short term slowing, versus gradually slowing over long periods) you're still wrong. The moon has been generally slowing down for the past 4.5 billion years, not doing the exact opposite.

If the moon slowed down it would drift inward

If the Moon were losing energy it would fall into a lower orbit, not climb away. While it is true that higher orbits mean lower orbital speeds

I am Not arguing with you on the bolded part.
It is true that the farther out something is the slower it goes... but if it's slow enough it will lose its orbit and hit the Earth. Comprende?

 

[Perfection]

I am Not arguing with you on the bolded part.
It is true that the farther out something is the slower it goes... but if it's slow enough it will lose its orbit and hit the Earth. Comprende?

Yeah, I'm not arguing that if the the moon suddenly was slowed in its present orbit it wouldn't fall inwards.

I'm saying that that the processes that in the long term slow the moon down move the moon outwards.

But I'll grant that it's a bit moot whether the OP was asking about what were to happen if the moon were to suddenly slow down, or what would happen if the moon gradually slowed down as it is doing right now.

However, we're you go dead wrong is where you make this correction:

Where've you been for the past 4.5 billion years? It's doing the opposite!

This is blatantly false. The moon is (in general) slowing down!