We have learned that we live on Earth, that Earth has one moon, we have a Sun and there are 8 planets orbiting the Sun. Earth is part of a solar system that consists of moon, planets, asteroids, meteors etc. These objects orbit in space and is 'held together' because of gravity.
Lets gather some extra information on our Solar system.
The solar system is about 4.6 billion years old and scientists believe it all started with a 'big bang'.
- What do you believe? How was everything made?
- Can you remember the names of the planets in order from closest to furthest from the Sun? If you cannot remember it, look at some ways that will help you remember.
The first four planets (Mercury, Venus, Earth and Mars) are called the 'inner planets' and the last four (Jupiter, Saturn, Uranus and Neptune) are called the 'outer planets'. The inner planets are smaller than the outer planets and are mainly made up of rock and metal, where the outer planets are bigger, they are also called the 'gas giants' since they are mainly made up of hydrogen, helium and other gasses.
As of 2008, there are also five dwarf planets: Pluto, Ceres, Eris, Makemake & Haumea.
- Find a picture of each of the dwarf planets and at least one fact on each (we have done planets in the previous lessons)
- Was Pluto always known as a dwarf planet?
An asteroid belt is also part of the solar system and you will find one Mars and Jupiter and it is made up of asteroids of all shapes and sizes.
- What is an asteroid?
- What is the area between Jupiter and Mars called?
- How big is an astronomical unit?
- What is a dwarf planet and give an example of one.
Many years ago and for thousands of years before there were any telescopes that could see as far as the ones we have today, people believed that there were not a lot of things in outer space and that Earth was the centre of the Solar system.
Scientists like Copernicus and Galileo figured out that the Sun is actually the centre of the Solar system and that all the planets orbits around it.
The Sun contains 99.86 percent of the Solar System's known mass, with Jupiter and Saturn making up making up most of the rest. The small inner planets which include Mercury, Venus, Earth and Mars make up a very small percentage of the Solar System’s mass.
- What rises in the morning and sets in the evening? Why is the Sun important to us?
- The sun is a star/planet. It is bigger/smaller than Earth.
- How far away from Earth is the Sun?
- How long does it take the light from the Sun to reach Earth?
- The Sun is the largest/smallest object in the Solar system.