Smokey ! Mass doesn't change ! You're supposed to know that. If the ball has 5 kg of mass on Earth, then it has 5 kg of mass on the moon, on Pluto, in orbit, in free fall, on a roller coaster, in the grocery store, in church, in the shower, or in my sock drawer. Mass doesn't change ! WEIGHT depends on gravity, so it can change. MASS doesn't and can't.