gravity
The Moon is orbiting a planet; It is orbiting the Earth. The velocity /acceleration of the Moon and the gravitational pull between Earth and Moon are in balance, so the Moon remains orbiting the Earth. Similarly the Earth and Moon , as a binary system, orbit the Sun , and the acceleration and gravitational forces are in balance. So none of us collide.
The sun's gravity keeps them in orbit and prevents them from flying off into space. The planets travel quickly enough that they do not fall into the sun.
The Sun's gravity keeps the planets orbiting the Sun.
Gravity
Venus!
The Sun's Gravitational pull keeps the planets orbiting it, not flying into deep space.
Gravity keeps your feet on the ground. Gravity keeps all orbiting objects in orbit around the object they are orbiting. The force of gravity decreases as a square of the distance between two objects. Gravity is the weakest of the fundamental forces. Gravity is an attractive force between any two objects that have mass.
It keeps the ecosystem from flying off the face of the planet
The gravity of the sun an each moon's respective planet keeps them from flying into space.
the moon orbits around the planet, not the other way around; gravity keeps it orbiting
The Moon is orbiting a planet; It is orbiting the Earth. The velocity /acceleration of the Moon and the gravitational pull between Earth and Moon are in balance, so the Moon remains orbiting the Earth. Similarly the Earth and Moon , as a binary system, orbit the Sun , and the acceleration and gravitational forces are in balance. So none of us collide.
The answer is the same for the moons of Mars as it is for any orbiting object. Angular momentum keeps them up, and gravitation keeps them from flying away. Those are the two balanced forces.
The sun's gravity keeps them in orbit and prevents them from flying off into space. The planets travel quickly enough that they do not fall into the sun.
a path called the 'orbit' which you used as a verb in the question, but it's also the noun used to denote the path in which the planet keeps orbiting
Gravity and Inertia. The gravity keeps the planet, moon etc. going in a circle and inertia keeps it going (inertia is the tendency of a moving object to continue in a straight line or a stationary object to remain in place. If there was no gravity the planet, moon etc. would just go in a straight line but with gravity it pulls it in a circle like a string attached to an object at the center.
the thing that keeps you from flying off the planet, and the thing the makes apples fall. (as Sir. Issac Newton confirmed)
The Sun's gravity keeps the planets orbiting the Sun.