A solar system consists of a star and objects that orbit it, bound to the star by gravity.
In our solar system, we call the star the Sun. Orbiting the Sun in our solar system are four main groups of objects: planets, dwarf planets, satellites, and comets and asteroids.
Planets are the largest objects in the solar system (not including the star). There are eight in our solar system.
In order to be a planet, these objects need to conform to three rules:
Here are the planets in order:
The planets of our solar system
There are three main types of planet in our solar system.
Pluto used to be considered a planet, but it doesn’t meet the third rule. It is not large enough to have cleared other large objects nearby. It was demoted to a dwarf planet in 2006. A dwarf planet is the name given to a celestial object that is similar to a planet, but hasn't met the criteria that would deem it a planet.
Satellites orbit planets. They can be natural, like the Moon, or man-made. Man-made satellites have been sent from Earth to orbit our planet or another in order to collect or relay information.
A weather satellite orbiting Earth
An asteroid is an irregularly shaped object which orbits the Sun. Asteroids are usually made from rocks or metal. There is a large area filled with asteroids between Mars and Jupiter called the asteroid belt.
When an asteroid enters Earth’s atmosphere, we call it a meteor. Usually these burn up in the atmosphere, but on very rare occasions they can reach Earth’s surface, where they’re called meteorites.
Just like an asteroid, a comet is also an irregularly shaped object which orbits the Sun. However, comets are made from ice and frozen gases like carbon dioxide. They are sometimes referred to as ‘icy dirtballs’. They orbit the Sun but most don’t come near Earth.
According to the National Curriculum Science objectives, children start to learn about the solar system in KS2. It is assigned as compulsory learning in Year 5 under the 'Earth and Space' strand of learning.
In Year 5, children should learn to:
In the non-statutory guidance, it is suggested that pupils should learn that the Sun is a star at the centre of our solar system and that it has eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune (Pluto was reclassified as a ‘dwarf planet’ in 2006).
In addition to our Year 5 Science scheme of work, Earth and Space, we also have an upper KS2 cross-curricular Space Topic, which includes 18 ready-to-teach lessons. If you are looking for space-themed English lessons, you might like our Stories from Space: Descriptive Writing scheme of work for Year 5.
