HISTORY OF ASTRONOMY

ARISTOTLE

• Thoght it was a geocentric universe
• Believed that planets and stars were perfect spheres, earth wasn't
• one of first to study plants, animals, and people in a scientific way
• Planets and stars circle forever in circular motion
• Called "The Grandfather of Science"

ARISTARCHUS

• Earth rotates on its axis & revolves around the Sun
• measure the relative distances between Earth and Sun/Moon
• lacked the technological equipment to make a precise measurement.

PTOLEMY

• Believed in Earth centered universe
• All astronomical objects move at constant speeds in circular orbits
• Created the Ptolemaic system model

COPERNICUS

• concluded that the Sun was the center of the universe instead of Earth
• felt that the Ptolemaic system was contrived
• he kept the orbits circular

KEPLER

• believed in the Copernican model of the universe
• 1st law) elliptical orbits to describe the motions of the planets
• line from Sun to planet sweeps out equal areas in same amounts of time
• the square of the number of years of a planet's orbital period is equal to the cube of that planet's average distance from the Sun
• 3 laws

GALILEO

• father of observational astronomy
• noticed the huge number of stars making up the Milky Way
• four moons orbiting Jupiter, Galilean moons
• Galileo's support of the Copernican model of the universe frightened the Church

THE END