Physics GCSE- Topic 1
Changing Ideas about the Solar System
Ancient Greeks used to make a observations using the naked eye and claimed that from these observations they knew that the Earth was the centre of the Universe and that everything orbited it eg. stars, sun, planets, moons etc. It was Ptolemy, a greek arstronomer, who introduced this idea and called it the Geocentric Model.
It wasn't until the 1500's when the Heliocentric Model began to replace the Geocentric one. The heliocantric Model suggested that these scientific observations could be explained without having the Earth at the centre of the Universe. Although this model had been around for about 2000 years it was first properly introduced by Nicolas Copernicus in his book which was written in 1543. He claimed that in fact the Sun was the centre of the Universe and that the Earth and planets orbit it. He also claimed that the stars remmained in a fixed position in a circle surrounding the Solar System.
Copernicus' ideas were not popular and his work was condemned by the church as they claimed that he had no evidence behind his theories. However, in 1610, Galileo was observing Jupiter using a telescope (a new invention at the time) and he noticed three stars in a line near the planet. When he looked again the next evening he saw that the stars had…