1. “If I have seen further it is by standing on the shoulders of giants.”
Ch. 3: The Solar System Sec. 1: Intro to the Sol Sys Part A: History of Astronomy
“If I have seen further it is by standing on the shoulders of giants.”
Sir Isaac Newton

2. History of Astronomy Early view (1st 6000 years)
Geocentric (Earth (man)-centered)
constellations (seasons)
“wanderers” (6 planets)
most moved east....but some were “retrograde”
Heavens are perfect, imperfection only lies on Earth

3. Aristotle ( BC)
celestial spheres
Spherical Earth

4. Eratosthenes ( BC)
Wikipedia

5. Ptolemy ( AD)
Almagest – Ptolemaic System
deferent and epicycles

6. Nicolaus Copernicus (1473-1543)
Polish priest
calendar fix
“On the Revolutions of the Celestial Spheres” (dedicated to the Pope)
Heliocentric – Copernican System
explains retrograde motion
Retrograde Animation
Retrograde Animation 2 + MORE
Both retrograde simultaneously
world view change

7. Tycho Brahe (1546-1601) Danish nobleman Uraniborg on Hven
- observation and
meticulous data

8. Johannes Kepler (1571-1630) German mathematician, astronomer
3 Laws of Planetary Motion
1) elliptical orbits
2) equal area law
3) harmonic law
- period2 = distance3
- astronomical unit (AU)

9. Galileo Galilei (1564-1642) Italian physicist, astronomer, philosopher
“father of modern astronomy”
Telescope
Lippershey (1608)
Discoveries (1609 onward)
craters on Moon
Sunspots
Galilean moons
Europa, Callisto, Ganymede, Io
***phases of Venus***
Outspoken supporter of Copernican model
Church problems
1632: Simplicius in “Dialogue Concerning the Two Chief World Systems”
1992: John Paul II

10. Sir Isaac Newton (1642- 1727) English physicist, etc...
1687 “Philosophiae Naturalis
Principia Mathematica”
(“Mathematical Principles of
Natural Philosophy”)
brought work of Copernicus, Galileo and Kepler together
Quote: “If I have seen further it is by standing on the shoulders of Giants.”
3 Laws of Motion and the Law of Universal Gravitation
- 1781: Uranus (Herschel)
- 1846: Neptune (Galle)
- 1930: Pluto (Tombaugh)

11. Albert Einstein (1879-1955) German/Swiss/American physicist
1905: Special Relativity and E=mc2! (+ 2 other papers)
1915: General Relativity: “curvature of space and time”
Time Magazine’s Man of the Century – 20th century

12. Stephen Hawking (1942- ) British cosmologist/physicist ALS Black holes
science accessibility
A Brief History of Time
A Briefer History of Time