Two factors that keep the planet and moon in orbit?

Answer 1

The mutual force of attraction between them due to gravity.

That the only factor it takes, which is fortunate, because that's the only factor there is.

Comment: There is another factor that's essential. It's "inertia".

Answer 2

1:mass of the planet

2:mass of the moon

gravity is the force of attraction between all objects with mass. bodies in orbit will continue to orbit unless a stronger force is introduced.

Answer 3

Those would be "gravity and inertia". Gravity attracts the Moon and Earth to each other, providing centripetal acceleration. The Moon is continually "falling" toward Earth, but centrifugal "force", caused by the Moon's inertia, keeps the Moon from leaving its orbit. Earth's orbital motion is so slight as to be ignored for everyday purposes. The Earth actually revolves around the center of mass of the Earth and Moon, and that's actually within the Earth.

If you were to take a string and tie a little weight on the end, you could whirl it round and round yourself. The string is like the Earth/Moon gravity, and the pulling you feel by the hand holding the string is the centrifugal "force".

Comment: It's not exactly obvious what the "orbits" in this question are. Maybe one is the Earth's orbit around the Sun. Anyway it doesn't really affect the basic ideas in the answer.

Answer 4

The force of gravity between two objects is completely determined by their masses

and the distance between their centers. Nothing else matters. It doesn't even matter

if there's something else between them ... you can't 'shield' against gravity.

The force of gravity is completely responsible for the existence and nature of the

orbital motions of planets, moons, comets, asteroids, etc.

Answer 5

Two factors that keep Earth orbiting the sun are the inverse square law of gravity and Newton's laws of motion.

Answer 6

Gravity and inertia

Gravity and inertia

Answer 7

1) The gravitational attraction between the planets and Sun.

2) The velocities of the planets at any instant (at a tangent to their

orbital paths).

Answer 8

Gravity is the force that keeps the moon t in orbit. Centrifical forces keep the planets in orbit. These foces keep everything spaced out where they should be and prevent any mishaps.