gcsescience.com 4 gcsescience.com
What is a Planet?
A planet is a
natural
satellite of a star.
There
are eight
planets
in our solar system.
All of the planets in our solar
system orbit the Sun.
The planets themselves do
not give
out light.
We can see some of the planets in the night sky
because they reflect sunlight
(like our moon
does).
The planets are so far away that they appear to
us like dots of light.
They look to our eyes like stars.
The orbit of a planet is
almost circular.
All of the
planets (except
Mercury) orbit in the
same plane.
The picture below shows the
solar system.
The relative size of the planets is indicated
but the Sun is very much larger than shown.
The picture also shows Pluto
in an elliptical orbit.
Pluto is a dwarf planet.
Click on a planet for more
information.
Links
Planets
The Solar System
Revision Questions
gcsescience.com Physics Quiz Index Solar System Quiz gcsescience.com
Home GCSE Chemistry GCSE Physics
Copyright © 2015 gcsescience.com. All Rights Reserved.