The Solar System

Our local neighborhood in Space is called the Solar System. At its heart is the Sun, an ordinary star that is so close that it floods our planet with light. Trapped in its orbit by gravity are Earth and seven other planets, their many moons, and millions of comets and asteroids

The Sun's family 

The solar system is a vast disc of material over 30 billion km (19 million miles) across, with the Sun

at its center. Most of it is empty space, but scattered throughout the countless solid objects bound to the Sun by gravity and orbiting (traveling around) it, mostly in the same direction. The biggest objects are almost perfectly round and are called planets. There are eight of them, ranging from the small rocky planet Mercury to gigantic Jupiter. The Solar System also hundreds of moons and dwarf planets, millions of Asteroids, and possibly millions or billions of comets.

The Sun and Planets

The sun is huge compared to even the biggest of the planets. Jupiter and it contains 99.8 % of the Solar System's entire mass. At nearly 1.4 million km (870,000 miles) wide, the Sun is ten times wider than Jupiter and over 1000 times massive. Yet even Jupiter is gigantic compared to Earth. The Solar System's eight planest form two distinct groups. The inner planets - Mercury, Venus, Earth, and Mars
- are solid balls of rock and metal. In contrast, the outer planets are gas giants - enormous, swirling globes mode mostly of Hydrogen and Helium.

Orbital Plane