newton's first law
newton first law of motion states: A body in motion tends to remain in motion, a body at rest tends to remain at rest unless acter on by an outsite force
so, ifan object is moring its inertia [mass] will tend to keep it in motion, and if some thing is at rest, its inerfia will few to keep it at rest from the goddard space center. learn more a bout newton's first law. checleout these additional ideas.