The Solar system!
•
You need to know about how peoples
ideas about the solar system have
changed.
Changing Ideas About the
Solar System
•
•
•
Ancient Greeks thought that earth was
the centre of the Solar System.
This model was called the Geocentric
Model.
This model was proposed by Ptolemy.
This model lasted for over
2000 years!
•
It only began to be replaced in the
1600’s
The New Model
Heliocentric models
•
Sun-centred (heliocentric)
•
Proposed by Copernicus (1473-1543)
•
Orbits are still taken to be circular
Galileo
Back when the model was first proposed, not
many people believe it to be true
"All truths are easy to
understand once they are
discovered; the point is to
discover them."
‘I will prove the Heliocentric
Model!’
Galileo’s observations
•
•
There are mountains on the moon
Venus has phases (like the moon) and
appears to change size
•
Jupiter has objects orbiting it (moons)
•
There are dark spots on the sun
•
The sun rotates and the spots on the
surface move
Galileo in trouble
•
In 1633 he was tried by the catholic Church
and forced to recant his ideas. He remained
under house arrest for the rest of his life
Is the model still the same
now?
•
•
We now know that the heliocentric
model is correct.
However the only difference is now we
know the orbits are elliptical rather
then circular.