astronomers : Java Glossary



Some of the very early astronomers figured out how the solar system works long before the general public did.

Astronomer Born Died Age Discovery
Aristarchus of Samos310 BC230 BC80 How eclipses work. That the earth revolves around the sun. That stars are suns. Ordered planets by distance from the sun. Computed relative distance to the moon and sun.
Ptolemy90 AD168 AD78 Worked out geocentric mathematics to predict planetary positions. He was primarily an astrologer.
Nicolaus Copernicus1473-02-191543-05-2470 Worked out a mathematical description of heliocentrism.
Tycho Brahe1546-12-141601-10-2454 Created a meticulous log of planetary observations. This was the raw data that Kepler used. Discovered supernovae.
Galileo Galilei1564-02-151642-01-0877 Discovered Jupiter’s moons. Got in hot water for popularising heliocentrism.
Johannes Kepler1571-12-271630-11-1558 Discovered that planets travel in ellipses. Worked out the math to predict how fast a planet travels at any given time.
Edwin Hubble1889-11-201953-09-2863 Using Doppler red shift, showed the universe was expanding.

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