Astronomers making careful observations of the moon’s orbit discover that the orbit is not perfectly circular, nor is it elliptical. which of the following statements supports this observation?
a. The moon and the planet exert forces of equal magnitude on each other
b. There is another celestial body that exerts a gravitational force on the moon
c. The value of the gravitational constant G is different in the location near the planet moon system
d. There is a centripetal force that causes the net force exerted on the moon to be different from the gravitational force



Answer :