A kind of push or pull on an object. A force causes an object to accelerate in the direction of the force.
The force that exists between all objects because of their mass. The force of gravity acts to pull objects.
Newton's First Law of Motion
This is a scientific principal first described by Sir Isaac Newton, which states that an object in a state of uniform motion stays in that state unless acted upon by an outside force.
The pathway of an object around another, such as the Moon around the Earth or planets around the Sun.
The turning of a planet on its axis.
The movement of a planet or Moon around another body, such as the Sun or a planet.