# Nudging Earth's Moon?

• December 31st, 2012, 08:27 AM
scoobydoo1
Nudging Earth's Moon?
I was kind of torn between posting this in the astronomy section or here, but I figured in the end that this section seems most appropriate. So here goes my question: What kind of or how much force would it take to nudge our moon off course (i.e. a comet collision, setting off a whole lot of nukes on the surface, attaching an incredible amount of booster rockets, or solar sails, etc?)?

I guess what I'm trying to wrap my mind around is would this force be powerful enough to wreck the moon apart before it departs from Earth's orbit, or is it possible for it to depart (relatively?) intact. :bugeye:
• December 31st, 2012, 11:00 AM
Janus
Any amount of force would be sufficient to do it, as long as it was applied over a long enough a time.

As an example, a single Saturn V booster could do it in ~30 billion years. (It would also need to burn more than 1/2 of the Moon's mass in fuel to do so.)
• December 31st, 2012, 11:54 AM
scoobydoo1
Quote:

Originally Posted by Janus
Any amount of force would be sufficient to do it, as long as it was applied over a long enough a time.

As an example, a single Saturn V booster could do it in ~30 billion years. (It would also need to burn more than 1/2 of the Moon's mass in fuel to do so.)

In other words, a sustained burn from a booster rocket over an extreme period of time (something along the lines of billions of years) could nudge the Moon away from Earth's orbit? Wow. :shock:

I would never have imagined that something like that could complete with Earth's gravitational pull on it's Moon. Thanks for the input. :oops:
• January 1st, 2013, 02:05 AM
Lynx_Fox
It's leaving anyhow....
• January 1st, 2013, 06:07 AM
scoobydoo1
Quote:

Originally Posted by Lynx_Fox
It's leaving anyhow....

It is drifting away from Earth's orbit?
• January 2nd, 2013, 09:27 PM
Lynx_Fox
Yes. For now it's trading the Earth's rotational momentum for an increasingly distant orbit. Eventually, given a lot of time, either the moon will be in a distant orbit with Earth and Moon gravitationally locked both having month long days, or the moon will escape.
• January 3rd, 2013, 02:46 AM
John Galt
I don't believe any of the outcomes of the Earth-Moon system lead to a lunar escape. My recollection is that once the moon and Earth are tidally locked that the dynamics of the system would lead to a slow inward spiral of the moon towards the Earth. However, the timing for the tidal locking post-date, by billions of years, the sun's red giant stage, which is likely to mean an end for both.
• January 3rd, 2013, 03:04 AM
Neverfly
Laser Pointer

Just needs a little help to escape, that's all...