<p>If we had two moons in opposition of each other the only short term effect would be amplified tides. Long term it will accelerate the decay of Earth's rotational period.</p>

CC BY-SA 3.0
2016-06-26T21:00:22.067Z
Presumably their orbits would be some 0.6% faster to account for the additional gravitation so they wouldn't spiral in.   James Kilfinger's answer is more correct, over time the orbits would destabilize.   What would realistically happen is the Moons would collide after perhaps a few hundred orbits, or swing past each other changing each others orbits measurably.   In any case, 2 moons wouldn't be stable.  Most likely outcome is they'd hit each other.   Possible outcome, one would be ejected the other would move closer to the Earth.
userLTK
CC BY-SA 3.0
2016-06-26T10:05:45.213Z
2016-06-26T10:05:45.213Z
Tanenthor
<p>An orbit as you describe is not stable. Even if the two moons are intially exactly the same distance from the Earth, small perturbations from the sun and other planets will cause one of them to speed up and the other to slow down. Eventually either one of them will hit the other, or one of them will hit the Earth. Whichever happens, it's not good.</p>

CC BY-SA 3.0
2016-06-26T17:47:22.297Z
2016-06-26T17:47:22.297Z
James K
<p>Can any one explain to me What will happen to Earth if its has two moons?</p>

<p>Same Distance &amp; two sides of earth (North &amp; south)?</p>

<p>Will it be good for humans or bad?</p>

CC BY-SA 3.0
2016-06-26T13:00:26.980Z
An excellent place for questions like this, Ransa, is the *worldbuilding* site. You could ask there.
Fattie
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2016-06-26T13:11:47.720Z
are you admin?.
RANSARA009
CC BY-SA 3.0
2016-06-26T14:01:26.430Z
Worldbuilding does indeed have a lot of questions of this type. A [search for "two moons"](https://worldbuilding.stackexchange.com/search?q=two+moons) gave me a lot of relevant questions.
SE - stop firing the good guys
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2016-06-26T16:00:25.940Z
I'm not an admin - I'm not even sober!!  :)
Fattie
CC BY-SA 3.0
2016-06-27T14:09:43.637Z
@RANSARA009 Admins (moderators/mods) like myself are not the only judges here. The community is the primary judge, so you should listen to the advice that you are given. If you don't attract many upvotes, it is likely because your question is viewed as too speculative for this site, more appropriate for Worldbuilding SE.
called2voyage
CC BY-SA 3.0
2016-06-27T14:40:09.363Z
@ Called2voyage is this a request or threatening? "Joe Blow" he is a one person in this site his not full comunity. so if 10 or 100 people say i will listen.. thanks 4 ur time
RANSARA009
<the-moon><earth>
Two moons and one Earth?
RANSARA009
# Two moons and one Earth?

(Asked by: username_0 on 2016-06-26)

Can any one explain to me What will happen to Earth if its has two moons?

Same Distance & two sides of earth (North & south)?

Will it be good for humans or bad?

**Tags:** the-moon, earth

> **Comments:**
> **username_1**: An excellent place for questions like this, Ransa, is the *worldbuilding* site. You could ask there.  
> **username_0**: are you admin?.  
> **username_2**: Worldbuilding does indeed have a lot of questions of this type. A [search for "two moons"](https://worldbuilding.stackexchange.com/search?q=two+moons) gave me a lot of relevant questions.  
> **username_1**: I'm not an admin - I'm not even sober!!  :)  
> **username_3**: @username_0 Admins (moderators/mods) like myself are not the only judges here. The community is the primary judge, so you should listen to the advice that you are given. If you don't attract many upvotes, it is likely because your question is viewed as too speculative for this site, more appropriate for Worldbuilding SE.  
> **username_0**: @ Called2voyage is this a request or threatening? "Joe Blow" he is a one person in this site his not full comunity. so if 10 or 100 people say i will listen.. thanks 4 ur time  

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## 2 answers

### Answer by username_4 on 2016-06-26. Score: 0 | Accepted answer

If we had two moons in opposition of each other the only short term effect would be amplified tides. Long term it will accelerate the decay of Earth's rotational period.

> **Comments:**
> **username_5**: Presumably their orbits would be some 0.6% faster to account for the additional gravitation so they wouldn't spiral in.   username_6ilfinger's answer is more correct, over time the orbits would destabilize.   What would realistically happen is the Moons would collide after perhaps a few hundred orbits, or swing past each other changing each others orbits measurably.   In any case, 2 moons wouldn't be stable.  Most likely outcome is they'd hit each other.   Possible outcome, one would be ejected the other would move closer to the Earth.  

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### Answer by username_6 on 2016-06-26. Score: 3

An orbit as you describe is not stable. Even if the two moons are intially exactly the same distance from the Earth, small perturbations from the sun and other planets will cause one of them to speed up and the other to slow down. Eventually either one of them will hit the other, or one of them will hit the Earth. Whichever happens, it's not good.


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