The Solar System
All the planets take different amounts of time to get all of the way around the sun. All of the planets spin while they move around the sun. The asteroid belt also spins around the sun.
The inner planets such as Mercury, Venus, Earth, and Mars are called terrestrial planets. The closest 4 planets to the sun are called the terrestrial planets because they are the planets that have the hardest surface. The sun could be called the center of our solar system because it is in the middle. The solar system is about 4.5 billion years old. It has 9 planets 5 rock and 4 gas planets. The 5 rock planets are the smallest planets and the 4 gas planets are the biggest.
All 4 of the planets that are gas planet have rings, all of the 5 other planets that are rock have no rings at all. All of the gas planets are almost like quick sand because if you were to stand on it you would sink.  Jupiter, Saturn, Uranus and Neptune are called the Jovian planets, they are called this because they are almost like Jupiter. There are maybe more than 102 moons in the solar system.