Historical Foundations of Astronomy

“If I have seen farther than others, it is because I have stood on the shoulders of giants” – Isaac Newton

Astronomy and Human Society

Measuring timeKeeping track of seasons (important for

agriculture)NavigationMythology/CosmogonyTechnology

Measuring Time

The Moon and Rainfall Patterns

Measuring the Seasons

Stone Circle in Callanish, The Hebrides, Scotland

“Sun Dagger”

Big Horn Medicine Wheel, Wyoming

“Templo Mayor”, Tenochtitlan

“When you notice the daughtersof Atlas, the Pleiades, rising, start on your reaping, and onyour sowing when they aresetting.”

-- Hesiod,Works and Days(800 B.C.E.)

Mayan Observatory at Chichen Itza, Yucatan

Navigation

Mythology

Technology

The Origin of Modern Science

Eratosthenes Measures the Earth

The Library at Alexandria

The Heavenly Spheres

Ptolemy’s

ModelUniverse

“Epicycles”

The Copernican Revolution

Born in Poland, 1473Developed a Sun-centered

Model for the UniverseStill assumed circular

orbitsNot much more accurate

(or simple) than Ptolemaic Model

Tycho Brahe (1546-1601)

Kepler (1571-1630)

Kepler’s First Law

Law of Equal Areas

Kepler’s Third Law

Galileo (1564-1642)

Galileo’s Telescopes

Phases of Venus

Epicycle Model

Heliocentric Model

Moons of Jupiter

Isaac Newton (1642-1727)

Universal Law of Gravitation