Solar system
From Simple English Wikipedia, the free encyclopedia
A solar system is a phrase used in astronomy. It means a star in outer space with planets and comets moving around the star. The best known solar system is the one humans live in, the one Earth is in. The Earth moves around the Sun in an oval shaped, or "elliptical" orbit. The other planets in the solar system also move around the sun in elliptical orbits.
The biggest objects that go around the Sun are called planets. It took people many years of looking carefully through telescopes to find them. No new big ones have been found for a long time, but more small objects are found every year.
[edit] Pluto is no longer a planet
Pluto has been called a planet for almost a hundred years. In 2006, astronomers decided Pluto should no longer be called a planet because it is so small. Also, its orbit is very different from the other eight planets.
Pluto, along with Ceres and Eris, is called a dwarf planet now.
[edit] The order of planets
These are the 8 planets, 3 dwarf planets and other large objects moving around the Sun in order from closest to the sun to farthest away from the sun:
There are also other things moving around the sun and they are all part of the solar system together. For example, the Asteroid belt. The Asteroid belt is a region with many rocks. These are much smaller than planets. Many are less than one kilometer across in diameter.
[edit] External links
| The Solar System | |
|---|---|
| Star | The Sun |
| Planets | Mercury • Venus • Earth • Mars • Jupiter • Saturn • Uranus • Neptune |
| Dwarf planets | Ceres • Pluto • Eris |
| Small solar system body | Asteroid belt – Comets – Meteors – Kuiper belt – Scattered disc – Oort cloud |
| Other | Moon |
