Gravitational forces as described by Newton's Universal Law of Gravitation.
Also important is the inertia of the planets and Newton's First Law of Motion is involved there.
The two forces that work together to keep the planets in orbit around the sun are gravity and inertia.
The Sun has a powerful gravitational pull. This, combined with the velocities of the planets, keeps the planets in orbit.
Planets, asteroids, meteors, comets, moons (which are also in orbit around their respective planets), dust particles, interplanetary gas.
It keeps them in orbit.
the suns gravity keeps the planets in orbit
Gravity is the force that holds a planet in orbit around the sun. Inertia keeps the planets spinning.
The Sun's strong gravity keeps all the planets in orbit around it.
The force of gravity keeps the Earth (and all the other planets) orbiting the Sun.
gravity
Gravity and velocity (inertia) keeps planets in orbit around suns.
the gravitational pull from the sun keeps the planets and other small things in the orbit of the sun.(;
As the planets orbit the sun, its gravity keeps them from colliding