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1600 BCE
1
The earliest written records (i.e. history) were astronomical observations - Babylonians (~1600 B.C.) recorded the position of planets, times of eclipses etc. -
500 BCE
2
The ancient Greeks inherited astronomical records from the Babylonians and applied the data to construct a cosmological framework. -
480 BCE
3
Thales, founder of Greek philosophy and founder of the Milesian school of cosmologists (~480 B.C.) used this data to predict eclipses. -
220 BCE
4
Eratosthenes (220 B.C.) - The early Greeks knew the Earth was a sphere based on the shadow of Earth on the Moon during lunar eclipses. Eratosthenes proceeded to use this information to measure circumference of Earth. -
100 BCE
5
Hipparchus (100 B.C.) produced first star catalog and recorded the names of constellations. -
200
6
Ptolemy (200 A.D.) was the Librarian of Alexandria who resurrected Heraclides geocentric theory and combined with centuries of data on planetary motions to predict the motions of the solar system -
1500
7
Copernicus (1500's) reinvented the heliocentric theory and challenged Church doctrine. By placing the Sun at the center of the Solar System, Copernicus forced a change in our worldview = paradigm shift or science revolution. -
1580
8
Tycho Brahe (1580's) was astronomy's 1st true observer. He built the Danish Observatory from which he measured positions of planets and stars to the highest degree of accuracy. -
9
Kepler (1600's) was a student of Tycho who used Brahe's database to formulate the Laws of Planetary Motion which corrects the problems of epicycles. -
10
Galileo (1620's) developed laws of motion -
11
Newton (1680's) developed the law of Universal Gravitation, laws of accelerated motion, invented calculus (math tool), the 1st reflecting telescope and theory of light. -
12
18-20th century, with discovery of the outer planets and where astronomy moves towards discoveries in stellar and galactic areas. -
13
Early 1960's with NASA deep space probes