The Moon and Mercury 

Scorched and Battered Worlds 
So the force pulling on you (suppose you are M_{2}), on the surface of the Moon, would be proportional to M_{1} / R^{2}, or the mass of the Moon divided by the distance to the center of the Moon, squared.
Since the Moon has about 1/80 of the mass of the Earth, and it has about 1/4 of the radius of the Earth, gravity on the surface would appear about (1/80)/(1/4)^{2} = 1/5 as great as on the Earth. (a more accurate estimate comes out to 1/6.)
Planet order from Sun 
1 
Golden Globe Awards for Mercury 

