A rock is moving through interstellar space towards a snow ball. Describe the motion of the rock until it hits the snow ball (in terms of Newton’s First Law). According to Newton’s 3rd Law, what will be the reaction to the force of the rock on the snow ball? How will these two forces compare?

Question

A rock is moving through interstellar space towards a snow ball.  Describe the motion of the rock until it hits the snow ball (in terms of Newton’s First Law).  According to Newton’s 3rd Law, what will be the reaction to the force of the rock on the snow ball?  How will these two forces compare?