Transcript SPACE SCIENCE UNIT 2 LESSON 1

SPACE SCIENCE UNIT 2 LESSON 1
Historical Modes of the Solar System
Solar system – the sun and all of
the bodies that orbit it
Models of the solar system
1. Heliocentric – the sun is the center of our
solar system
2. Geocentric – the earth is the center of our
solar system
3. Parallax – The apparent shift in the position
of an object when viewed from different
locations
Aristotle –
Greek philosopher
384-322 BCE
• Geocentric model
• Parallax
Aristarchus – Greek Astronomer and
Mathematician
310-230 BCE
• Heliocentric
• Not widely accepted
• Attempted to measure
relative distances to the
moon and sun
Ptolemy – Egyptian Astronomer and
Mathematician
100-170 CE
• Geocentric
• His book was based observations going back
800 years
• First detailed model of geocentric model (used
for the 14 centuries)
• Celestial bodies travel at a constant speed
• Orbits perfect circle
• “Wheels on Wheels” system
Copernicus – Polish Astronomer
1473-1543
• Heliocentric
• Made first detailed model of heliocentric
model
• First step in the modern model
• Orbits perfect circles
• “Wheels on Wheels” system
Brahe – Danish Astronomer
1546-1601
• 20 years of observations of the planets
Kepler – German Astronomer
1571-1630
• Heliocentric
• Used Brahe’s observations
• 3 laws of planetary motion
– 1. elliptical orbits
– 2. closer to the sun the fast planet revolves
– 3. Farther from the sun takes longer to orbit
Galileo – Italian scientist
1564-1642
• Heliocentric
• Used scientific method
• Evidence for heliocentric model
– Found 4 natural satellites of Jupiter
– Found that Venus goes through phases
– Not all bodies in space revolve around earth