Presentaci

1
Explanations full of superstitions and myths
Astronomy begins (science)
Two astronomic models fourteen centuries apart
Heliocentric(Copernicus)
Geocentric(Ptolemy)
Both were wrong nowadays the modern model is
accepted according to which the Earth revolves
around the Sun. The Sun is only one star out of
the thousands of millions that form the universe.
Finish
2
Ptolemys geocentric model (2nd century A.D.)

1. The Earth is at the centre of the Universe, it is
   spherical and it does not move.
2. The Sun, the Moon and the planets move around the
   Earth in circular movements.
3. The stars are fixed in a far away sphere which
   moves around the Earth.

3
Copernicuss heliocentric model (16th century A.
D.)

1. The Sun is at the centre of the universe and it
   does not move.
2. The Earth rotates on its own axis and the Moon
   revolves around it.
3. The Earth and the rest of the planets revolve
   around the Sun at different speeds and in
   concentric circles.
4. The sphere of stars that surrounds this system
   does not move.