The Solar System

In short: The Solar System consists of the Sun, eight planets, their moons, dwarf planets, asteroids and comets. It formed about 4.6 billion years ago from a cloud of gas and dust.

In more detail: The Sun contains almost 99.9 percent of the total mass. Its gravity keeps all bodies on their orbits.

In detail

• Inner planets: Mercury, Venus, Earth, Mars. Rocky planets with solid surfaces.
• Outer planets: Jupiter, Saturn (gas giants), Uranus, Neptune (ice giants).
• Asteroid belt: Between Mars and Jupiter millions of rocky bodies orbit. Ceres is a dwarf planet.
• Kuiper belt: Beyond Neptune lie icy bodies such as Pluto.
• Distances: Earth is about 150 million km from the Sun (one astronomical unit) (lichtgeschwindigkeit).