From determining that the Earth is round to discovering gravity, the theories of history’s earliest astronomers helped lay the foundation for today’s celestial sciences. 

In honor of Space Exploration Month, Questia, the premier online research tool for students, has granted access to reference works on five of history’s earliest astronomers for free for an entire month. 

  1. Aristotle:  Born in 384 B.C. in what is now the northern part of Greece, Aristotle spent much of his adult life in Athens and was a member of Plato’s Academy.  While the chronological order of Aristotle’s works are unknown, many of his lectures offer a dialectical examination of physics and nature as well as proponed theories on form and matter.  Aristotle’s claims of form and matter are the foundation for his most detailed accounts on substance, which also reflect his philosophy on the relation between mind, body and soul, as well as the nature of knowledge.  [Irwin, Terrence, et al.  Aristotle: Selections.  Hackett Publishing Company: 1995] 
  1. Plato:  A student of Socrates, Plato’s philosophy and theories of metaphysics and forms are well-recognized as well as his creation theories.  Plato’s creation story, Timaeus, explores themes on the formation of the universe using natural philosophy.  Plato suggested that the world was divinely created by a supreme deity, in a manner that similarly reflects today’s widely accepted “Big Bang” theory.  [Zeyl, Donald J.  Timaeus.  Hackett: 2000] 
  1. Galileo:  Known as the father of modern science, Galileo’s theories transformed Western culture and set the precedent for the Scientific Revolution.  Galileo’s contributions to space exploration include his view that the Earth revolves around the Sun, contrary to the religious belief at the time that the Earth was the center of the universe.   Galileo also improved upon the telescope and with it made several celestial discoveries, including studying the moons of Jupiter.  [Shea, William R.  Galileo in Rome: The Rise and Fall of a Troublesome Genius.  Oxford University Press: 2003] 
  1. Nicholas Copernicus:  Copernicus was a man of many trades, but is perhaps most remembered for his outlooks on astronomy and the universe.  Within the field of astronomy, Copernicus contributed his theory in which the solar system functioned; with the sun at the center moving the Earth, moons and planets.  Following the theory of light years and the Copernican conception, it was later discovered that the Earth is 93 million light years from the Sun.  [Mizwa, Stephen P.  Nicholas Copernicus, 1543-1943.  Kosciuszko Foundation: 1943] 
  1. Isacc Newton:  Some of Newton’s metaphysical concepts include absolute space, absolute time and absolute motion.  These notions explore the theory that space, time and motion are the work of celestial mechanics which are based on gravitational pull.  He recognized that the sun was the center of gravity within the solar system and that the planets move with an orbital motion in the form of an ellipse.  From orbital motion, Newtondeduced the theory of Universal gravitation in which is based on the compounding of celestial motions.  [Cohen, Bernard.  The CambridgeCompanion to Newton.  Cambridge University Press: 2002]

Visit Questia’s topic page on space exploration for more information on astronomers. 

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