Every object in existence has mass. Mass is a measurement of the amount of matter than an object has. Weight and mass, however, are not the same thing. Weight is calculated by multiplying an object's mass and its acceleration due to gravity. W = m × g Why is the weight of an object different from planet to planet? A. The mass of an object changes when it is on different planets. B. This statement is not true; objects have the same weight from planet to planet. C. The acceleration due to gravity varies from planet to planet. D. The amount of air varies from planet to planet.