Subject: What would it take as far as gravitational pull to hold life supporting...

I write as a hobby and would like to try a little short story 
about a
group of people on a space station orbiting the moon and working 
on
giving the moon a basis for water and atmosphere.  I'm not really 
too
serious as far as the scientific aspects as I just want to 
concentrate
on relationships of some fictional charectors that I could dream 
up.
But I thought it would be helpful to know what would it take as 
far as
gravitational pull to hold life supporting eliments on the moon.  
Would
the moon's spin on it's axis have to be sped up some how.  I saw 
that
the moon rotates 27 earth days.
I'm thinking of just entering a writing contest so it doesn't 
have to be
a really elaborate explination.  Just something to help give me a 
basic
understanding as to how much gravitional force is needed to keep 
water
and air on a rock floating in space.  Far fetched I know but I'm 
having
fun.  This is my first attempt at writing a little bit more with 
science
in mind.  I wrote some stories before and I like the challenge of 
being
diverse.  Thank you.
Terry J.

Re: What would it take as far as gravitational pull to hold life supporting...