Answer: The two main factors that determine a planet's orbit are the mass of the planet and the mass of the object it is orbiting (such as a star)
Explanation: The gravitational force between these two objects causes the planet to follow an elliptical orbit around the object. The planet's velocity, or speed, also plays a role in its orbit, as it determines the shape of the orbit. The shape of the planet itself does not significantly affect its orbit. The planet's volume may have some effect on its orbit if the planet has a high density and therefore a strong gravitational pull, but it is not a primary factor.