Solar System

• Planets - comes from a greek word planetai which means wandering
• Inner planets - Mercury, Venus, Earth, Mars
• Outer Planets - Jupiter, Saturn, Uranus, Neptune
• Inner planets are mostly made up of rock and metal, while the outer planets are mostly made up of gas.
• Inner planets have a diameter less than 13,000km
• Outer planets are also known as: gas giants
• Outer planets - mostly made up of gases (primarily hydrogen and helium)
• outer planets - very light for their size
• inner planets - have no rings and a few moons (if any)
• outer planets have rings and many moons
• outer planets have a diameter of 49,000km or greater
• revolution - the movement of the earth around the sun
• rotation - the movement of the earth on its own axis
• day and night - effects of earth's rotation
• it takes 365 ¼ for the earth to revolve around the sun
• Neptune is the coldest planet with a temperature of -201°C
• Venus is the hottest planet with a temperature of 480°C
• Venus and Earth are almost the same size
• Jupiter is the largest planet in the solar system
• Mercury takes 88 days to revolve around the sun
• Neptune takes 165 years to revolve around the sun
• Jupiter takes 10hours to rotate
• Jupiter has the most number of natural satelites with a number of 63
• mercury and venus have no natural satelites
• Comet - made up of dust and rock particles mixed with frozen water, methane and ammonia
• Rotation - movement of an object on its own axis
• Revolution - movement of an object around a bigger planet