EAPS 11600 Chapter Notes - Chapter 1: Nuclear Reaction, Planetary Nebula, Hydrosphere
15 Jan 2019
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Document Summary
Cosmology-the study of the overall structure of the universe. In answering questions, ancient philosophers learned to distinguish stars from planets. Came up with two models to explain the configuration of stars and planets to relationships to the sun, earth and moon. Geocentric universe concept-an ancient greek idea suggesting that the earth sat motionless in the center of the universe while the stars and other planets and sun orbited around it. Heliocentric universe concept-an idea proposed by greek philosophers around 250. B. c. e. suggesting that all heavenly objects including earth orbit the sun. Renaissance brought new thinkers about exploration and scientific discovery. Universe-all of space and all the matter and energy within it. Star-an object in the universe in which fusion reactions occur pervasively, producing vast amounts of energy; our sun is a star. Stars are pulled by gravity to galaxies. Galaxy-an immense system of hundreds of billions of stars. Solar system-our sun and all the materials that orbit it.
