HISTORY OF ASTRONOMY

ARISTOTLE

• If earth went around the sun the stars would move
• Came up with parallax
• Parallax means the shift in an objects position when viewed from other places

ARISTARCHUS

• Proposed a heliocentric model of the solar system
• Attempted to measure the distance between the moon and sun
• His ratio of distances was too small but he used observation

PTOLEMY

• Developed a geocentric model
• Believed in "wheels on wheels" system
• Wrote a book based on planets

COPERNICUS

• Developed the first detailed heliocentric model
• Model is first step to the modern models
• Believed in "wheels on wheels" system

KEPLER

• realized the motion of planets wasn't circular
• Formulated three principles: Kepler's laws
• Found out that Ellipses fit best

GALILEO

• Made a more powerful telescope
• Earth is not the only planet that orbits
• Studied Venus