As the Force of friction is equal to 
µ
by using the Law of Action Reaction; as the force normal is the conterforce of gravity
µ
µ
Therefore, by looking at the equation we can infer that
The force of friction is directly proportional to the mass, gravitational constant, and the co-efficent of friction
Because the gravitational constant is dependant on gravitation, a planet's mass and radius also affect the force of friction
But DO NOTE:
That the co-effecient of friction is only applicable between two rubbing surfaces and unaffected by gravitational constants.
If you found this helpful, please rate it as "Brainiest"
Also if this need further explaining, please comment below
Therefore, by looking at the equation we can infer that
The force of friction is directly proportional to the mass, gravitational constant, and the co-efficent of friction
Because the gravitational constant is dependant on gravitation, a planet's mass and radius also affect the force of friction
But DO NOTE:
That the co-effecient of friction is only applicable between two rubbing surfaces and unaffected by gravitational constants.
If you found this helpful, please rate it as "Brainiest"
Also if this need further explaining, please comment below