Gravity provides the force needed to maintain the stable orbit of planets around a star and also of moons and artificial satellites around a planet. The moons around planets in the Solar System ...

The Sun is the largest object in the Solar System. The Sun’s huge gravitational field keeps many other objects – planets, dwarf planets, asteroids and comets – in orbit around it.

When looking at our solar system, the planets going around the sun ... astronomers say that the position and motion of the planets is not exactly what they would expect given what we know about ...