Our solar system consists of an average star we call the Sun, the planets Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune. It includes the satellites of the planets; numerous comets, asteroids, and meteoroids; and the interplanetary medium. The Sun contains 99.85% of all the matter in the Solar System. Our solar system extends much farther than the eight planets that orbit the Sun. The solar system also includes the Kuiper Belt that lies past Neptune’s orbit.
There are two kinds of planets:
- Rocky planets include Mercury, Venus, Earth, and Mars which are mostly made up of solid rock and metal.
- Gas giants include Jupiter, Saturn, Uranus, and Neptune which are mostly made up of gases like Hydrogen, Helium, Methane, etc. These planets are very large in comparison to the rocky planets.
Our solar system formed about 4.5 billion years ago from a dense cloud of interstellar gas and dust. The cloud collapsed, possibly due to the shock wave of a nearby exploding star, called a supernova. Our planetary system is named the ‘solar’ system because our Sun is named Sol, after the Latin word for Sun, ‘Solis’, and anything related to the Sun we call ‘solar’.