Re: If our moon went flying off into space for some reason would it affect us?

Hello, Phillip.

You've asked two questions -

1. If the moon went flying off into space, would it affect us? and

2. Could such a thing happen?

To answer your first question, yes, it would affect us. But not much. Let me explain why.

The two most noticable effects we experience from the moon are its lighting up the night sky, and the tides. Another effect, less noticable, is the moon's influence on the earth's orbit around the sun.

Without moonlight at night tides, and a wobble in our orbit, life on earth wouldn't be much different. Our beaches would be dirtier, animals who hunt by moonlight would need to adapt or perish, but not much would change in the average person's everyday life.

Some people believe that the moon's presence influences the growth of crops, but since the moon has been in the sky ever since man started growing crops, we've never been able to test this belief.

Second, could the moon ever be moved out of its orbit? Well, I don't see how it could without catastrophic effects happening here. Any object that hit the moon hard enough to move it out of earth orbit would shatter it in the impact. A very large object passing near the moon could pull it out of orbit without destroying it, but the earth would be pulled out of orbit, too, probably into an orbit that would move temperatures outside of earth's life limits.

To move the moon without destroying it or disturbing the earth, gentle presure over a long period of time is needed. Mankind could probably do it using moon based fixed rockets, but I can't imagine a reason we would want to.

Layne Johnson

[Moderator's note: It would take a lot of energy to move the Moon. There's already been a question on the Mad Sci Network which calculates the energy required to move the Earth. It's far beyond even the most powerful rockets ever built. The Moon is about 1% of the Earth's mass, so would only need about 1% as much energy to move, but this is still beyond anythng that we could build.

There might be a change in the climate if the Moon weren't there. See this answer from our web site for a discussion.

Jim O'Donnell, jim@penfold0.demon.co.uk]