Exploring the Solar System The Planets of our Solar System

1. Exploring the Solar System The Planets of our Solar System

2. Objects in our Solar System How do scientists work out which object is a star, a planet or a moon?

3. Our Solar System Our Solar System consists of: A star, 8 planets, at least 5 dwarf planets, hundreds of moons, comets and asteroids.

4. The Terrestrial ‘rocky’ planets These planets are made up mainly of rock or metal. Rocky planets are generally smaller than Gas Giants and rotate slowly. They are Mercury, Venus, Earth and Mars. Should the Moon be in this list?

5. The Gas & Ice Giants Gas giants are huge! Jupiter, Saturn, Uranus and Neptune are formed mainly out of hydrogen and helium and spin quickly. They all have rings although Saturn’s are the most obvious. Why are Uranus and Neptune called the ice planets? Could the Earth have rings like Saturn?

6. Dwarf planets and asteroids Dwarf planets are objects that orbit a star and are spherical but NOTcleared its orbit of other objects. Pluto and Ceres are now classified as a dwarf planets. • Asteroids are found throughout the Solar System but most are between Mars and Jupiter in the Asteroid Belt. • They are chunks of rock, that orbit a star, but are not spherical. They are made up of the ‘left over’ bits when the Terrestrial planets were being formed. Many asteroids also have moons!

7. Comets Comets are icy bodies that are usually frozen and orbit far from the Sun. If they fall in towards the Sun they melt. As they melt they form large “tails” of dust and gas. Halley’s Comet is very famous. It was seen as a sign of doom in the Middle Ages and appears as a warning to King Harold. It can be seen on the Bayeux tapestry. All comet tails point away from the Sun just like your shadow!