According to Newton's second law of motion, a net force on an object will cause it to accelerate. How does the Newton's law relate to the force of gravity?

Newton's second law says that when a constant force acts on a massive body, it causes it to accelerate, i.e., to change its velocity, at a constant rate. In this case, the constant acceleration due to gravity is written as g, and Newton's Second Law becomes F = mg.

365.25 earth days are in the year of a light year