Space and Astronomy crossword

If an object is moving, you must have a frame of
This is an object that is moving and a background that is moving
An object is in when its position changes
position is the of an object in space ant it is always relative to a frame of reference
Gravitational is the force that attracts two objects
Gravitational force increases as the objects masses
is the amount of matter in an object
is a force that opposes motion
it either motion or slows it down
is the distance an object travels in a certain amount of time
something is moving
is the measure of an objects speed in a particular direction
a car traveling down a straight highway at a constant speed has velocity
we can also describe velocity as