The moon.

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The research says that the moon is getting away from the earth a few cm yearly, what will happen to the earth if we completely lose the moon?[?]
 

marcus

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Originally posted by Saint
The research says that the moon is getting away from the earth a few cm yearly, what will happen to the earth if we completely lose the moon?[?]
A slightly different question is
would multicell life have evolved on the earth if
it wasnt essentially part of a double-planet system

People might possibly dismiss Saint's question because
it will take a very very long time for the moon to get significantly farther away and life has already evolved here and if it survives its own vices and stuff it can certainly survive losing the moon but that is so far in the future it .....well


But suppose in another galaxy there was a star like the sun that had a planet like the earth with lots of good water and atmosphere and stuff----only this earth did not have a moon.

Would this be as hospitable to life?

Would, for example, that earth's axis be as stable as ours has been. Or would it wobble all around and wreck evolution by
huge swings in climate?

Are tides important to evolution. I dont have any idea myself but maybe somebody does. Anyway to me it seems like an interesting thing to ask. How might things have gone for us if the earth had not had its moon.

Important fact-----the moon is 1/80 of the mass of the earth.

Compared with that (a moon over 1 percent of your mass) Mars has zilch moon. Jupiter has zilch moons. Saturn's moons are negligible compared with the planet's mass. But Earth-Moon is, in a very real sense, a double planet.
 
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Originally posted by Saint
.... what will happen to the earth if we completely lose the moon?[?]
Uh, no more eclipses? Hmm?
No more seeing craters with my 35 year old 30X Tasco zoom telescope. or with Mount Polamar's 200 incher.

No more place for lunar landers to land.
No more lunar rocks to be brought back only to be stolen and offered for sale at outrageous prices on e-bay.

No more speculation whether life exists on the moon.
No more odd ball stories in Popular Mechanic's magazine about how we plan to colonize the moon in the next ten years.

No more worry about having to wait for darkness of 'new moon' before bombing the crup out of Iraq (or any other 'evil' dictator).

Best of all : No more lunar light pollution plaguing deep sky observation and astrophotography.

Yep, it going to be a boring place to live.

:frown:
 
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Re: Re: The moon.

Originally posted by marcus
Are tides important to evolution. I dont have any idea myself but maybe somebody does. Anyway to me it seems like an interesting thing to ask. How might things have gone for us if the earth had not had its moon.
very much so. several (hundreds or more) species are dependant on the motion of the tides for movement and food regulation and hundreds more are dependant on those creatures and so on and so on. it's the old web of life.
 
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If we had no moon, would our earth be much scorched?

As for other things, I believe the earth would spin faster, it wouldn't be in the same stable orbit, as for where it would go, I don't know.

Rotating faster would cause huge storm systems and high winds.

That's all I have to add
 
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Originally posted by kyle_soule

Rotating faster would cause huge storm systems and high winds.


i don't know if this is true. the earth is rotation very rapidly as it is, and our winds have little or no connection to this effect. but you are right, our orbit would change dramatically.
 
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Originally posted by maximus
i don't know if this is true. the earth is rotation very rapidly as it is, and our winds have little or no connection to this effect. but you are right, our orbit would change dramatically.
Hm...Jupiter rotates much faster, and very stormy weather, I was simply applying the same uneducated guess to the earth. I don't care much for thinking of "what-ifs" so I have not researched this subject, although I do know that Discovery had a show a long while back on this, and there is a book on it.

The wind comes from the air between pressure systems, I guess. Would the absense of the moon cause fewer clouds to form, as the majority of the water would be sitting still?
 
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Originally posted by kyle_soule
Hm...Jupiter rotates much faster, and very stormy weather, I was simply applying the same uneducated guess to the earth. I don't care much for thinking of "what-ifs" so I have not researched this subject, although I do know that Discovery had a show a long while back on this, and there is a book on it.


i also don't know to much on the subject, but i bet there are other reasons to describe the weather of jupiter.

The wind comes from the air between pressure systems, I guess. Would the absense of the moon cause fewer clouds to form, as the majority of the water would be sitting still?
this seems more plausable, but like i said, i'm no meteoroligist. i pupose water would still evaporate and form clouds, but the clouds might not move as much.
 

russ_watters

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Losing the moon will not cause in increase in the rotation rate - but it will cause a DECREASE in the rate the earth's rotation slows due to tidal friction.
 

Phobos

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marcus

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Originally posted by Phobos
fastest hijack ever!

According to astronomer Sten Odenwald...
http://itss.raytheon.com/cafe/qadir/q1282.html

The Earth will not completely lose the moon (the orbit will eventually stabilize).
this is a pretty nice fact----here's what it says at Phobos' link:

[[Is the Moon moving away from the Earth?

Yes it is, but very slowly. The current rate at which the Earth day is increasing is 0.0018 seconds/century. The semi-major axis of the lunar orbit is increasing by 3.8 centimeters/year according to laser ranging measurements made since the 1970's using the Apollo 'corner cube reflectors' deposited on the surface by the astronauts. It is expected that in 15 billion years, the orbit will stabilize at 1.6 times its present size, and the Earth day will be 55 days long equal to the time it will take the Moon to orbit the Earth. Of course, in less than 6 billion years, the Sun will have evolved into a red giant star and engulfed the Earth-Moon system, thereby incinerating it!]]

Executive summary: the moon will keep moving away until the sun goes red giant. (After that doesnt seem to matter)


This is interesting partly because it illustrates something about the transfer of angular momentum by tides. Tides slow down the rotation of the earth and pump angular momentum into the moon's orbit. As long as the day is shorter than the month----that is, as long as the earth's turning is faster than the moon's revolving----the tide mechanism gradually bleeds angular momentum out of the more rapid rotation and transfers it into the moon's orbit. This transfer of angular momentum swings the moon farther and farther out.

But (Phobos' link indicates) the transfer is so slow that it would not be finished for 15 billion years even if allowed to continue uninterrupted!---and long before then (namely by 6 billion years) the sun will
go red giant.

Apologies for my earlier post turning out to be off topic! I didnt mean to hijack but to add a dimension to the discussion namely what practical stuff does the moon do for us (besides look beautiful all the time.)
 
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