Ancient Astronomy Chapter 3

Mesopotamian Astronomy Lots of data on planetary cycles, regularities and periodicities observed in the sky. Babylonians ---Astrology. Predictions based on the influence of the Sun, Moon, and planets to natural events, i.e., floods, earthquakes, etc. Egyptian astronomy Greek Astronomy Miletus-Thales (600 BC), Anaximander, Anaximenes. Pythagoreans. New model of Solar system. Aristotle (384-322 BC) Aristarchus(300 BC), Eratosthenes (276-195) Radius of the Earth Hipparchus (134 BC) Catalog of brightest stars; Precession, his estimate 28,000 years. Ptolemy (127 AD). Accurate geocentric model, epicycles.

Planetary configurations in Babylonian astronomy.

Timetable of World Events and Famous People (Left) and Fig. 3.3 Timetable of World Events and Famous People (Left) and Notable Greek Astronomers (right)

Fig. 3.5 Pythagorean Model

Aristotle’s argument that the earth must be a sphere Fig. 3.7 Aristotle’s argument that the earth must be a sphere

Another Aristotle’s argument that the Earth is sphere Fig. 3.8 Another Aristotle’s argument that the Earth is sphere

Aristarchus’s (310-230 B.C) Calculation Fig. 3.9 Aristarchus’s (310-230 B.C) Calculation of Moon’s diameter and distance from Earth

Fig. 3.10 Small angle formula

Fig. 3.11

Fig. 3.12

Fig. 3.13

Fig. 3.14 Eratosthenes’s (276-195 B.C) calculation of the earth’s radius

Precession of the earth’s axis (Hipparchus (134 B.C) Fig. 3.15 Precession of the earth’s axis (Hipparchus (134 B.C)

Precession of the celestial equator Fig. 3.16 Precession of the celestial equator

Fig. 3.17 Ptolemy’s model

Fig. 3.18 The Geocentric Model

Fig. 3.19