Welcome to understanding how our solar system works. The solar system is a gravitational system centered around our Sun, a massive star that contains over ninety-nine percent of the system's total mass. The Sun's immense gravity pulls all objects toward it, while their sideways motion creates stable orbits around the central star.
Gravity is the fundamental force that keeps the solar system together. Objects orbit because they have forward motion, called inertia, and gravitational pull toward the Sun. The balance between these two forces creates stable elliptical orbits. As we can see, the planet moves forward while gravity constantly pulls it toward the Sun, resulting in a curved orbital path.
The solar system has eight planets orbiting at different distances from the Sun. The inner planets Mercury, Venus, Earth, and Mars are rocky worlds close to the Sun. The outer planets Jupiter, Saturn, Uranus, and Neptune are gas giants much farther away. An important principle is that planets closer to the Sun orbit faster than those farther away, as we can see in this animation.