What was ptolemys vision of how the universe worked

He published his observations which went against the established teaching of the Church. He was brought to trial and, although he made a confession of wrongdoing, he was still kept under house arrest for the rest of his life. But it was too late to lock away the knowledge that Galileo shared. Other scientists, including Sir Isaac Newton and Johannes Kepler, seized its importance and were able to learn even more about the ways of the world and the heavens beyond.

These early scientists' legacies continue to this day. As time goes on, we use our instruments, science, math, reasoning, and creativity to learn more about the secrets of the Universe. In this way, we are directly linked to the astronomers of times past who gave us direction to discover more about the dances of the planets and the nature of the stars. Makers of Science Volume one of this reference set has information on Aristotle, Copernicus, and Galileo.

Recentering the Universe An page round-up of how these early scientists' work changed everything about people understood their world. Articles on many early astronomers can be can be found in our online databases: Biography in Context and Encyclopaedia Britannica English, Spanish, and children's versions. Aristotle Leads the Way Captures the life and times of Aristotle, the ancient Greek philosopher who studied a wide range of subjects and helped shape early scientific beliefs.

In our young adult collection. The Great Thinker Stresses the importance of Aristotle's intellectual discoveries on the future of science.

Biography for Kids: Aristotle A short online biography of Aristotle good for upper elementary grades that touches on some important points. Copernicus An enjoyable page biography of the 16th-century Polish scientist that includes activities on retrograde motion, the solar system, parallax, and an astrolabe.

Nicolaus Copernicus The center of the universe -- A childhood in Poland -- A long-term student -- In the service of the church -- Look to the stars -- The Copernican theory -- Late in life -- A scientific revolution -- Late in life -- Life at a glance. The History News in Space Uses a newspaper format to take a look at developments that led from the ideas of Copernicus and other early scientists to the technological advances that enabled man to venture to the moon and beyond.

Galileo A biography of 17th-century Italian astronomer and physicist Galileo that includes related activities for readers. Galileo for Kids This biography has experiments and activities as well as his life story. Starry Messenger A beautiful retelling, in picture book format, of Galileo's story which can be used with both younger and older audiences. The Galileo Project A hypertext online source of information on the life and work of Galileo Galilei and the science of his time.

Includes a biography, letters from his daughter, and a tour of his home. From Rice University. Galileo's Battle for the Heavens An online timeline of his life, articles on his place in science and his telescope, his mistakes on predicting the tides, a teachers' guide, and interactives on his experiments with falling objects, projectiles, inclined planes, and pendulums. Who Was Galileo?

A page biography with illustrations and maps. Part of the "Who Was" series. Also available on eAudio. Ptolemy's World Lots of illustrations of Ptolemy's geography, a note on his principle of simplicity, and links to his texts. Skip to main navigation Skip to main navigation Skip to search Skip to search Skip to content. Use current location. See all locations. Admin Admin Admin, collapsed. Main navigation Events. Open search form.

Enter search query Clear Text. Saved Searches Advanced Search. Welcome Welcome, collapsed Welcome. Search the Catalog Can't Find It? Which planet travels the fastest? What observations did the geocentric model explain? What traits do all solar system model share? What trait do all solar system models chair?

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What is the 3 biggest planet? What is the 6 largest planet? What is the closest planet to Sun? How many planets are there in ? What is the next livable planet? Is there 8 or 9 planets? Who found the planets? Who discovered the moon? Who discovered space? An eccentric construction is one in which the Earth is placed outside the center of the geometrical construction. Here, the Earth, E, is displaced slightly from the center, C, of the path of the planet. Although this construction violated the rule that the Earth was the center of the cosmos and all planetary motions, the displacement was minimal and was considered a slight bending of the rule rather than a violation.

The eccentric in the figure below is fixed; it could also be made movable. In this case the center of the large circle was a point that rotated around the Earth in a small circle centered on the Earth. In some constructions this little circle was not centered in the Earth.

The second construction, the epicycle, is geometrically equivalent to the simple movable eccentric. In this case, the planet moved on a little circle the center of which rotated on the circumference of the large circle centered on the on theEarth.

When the directions and speeds of rotation of the epicycle and large circle were chosen appropriately, the planet, as seen from the Earth, would stop, reverse its course, and then move forward again. Thus the annual retrograde motion of the planets caused, in heliocentric terms by the addition of the Earth's annual motion to the motion of the planet could roughly be accounted for. But these two constructions did not quite bring the resulting planetary motions within close agreement with the observed motions.

Ptolemy therefore added yet a third construction, the equant. In this case, the center of construction of the large circle was separated from the center of motion of a point on its circumference, as shown below, where C is the geometrical center of the large circle usually called in these constructions the excentric circle but the motion of the center of the epicycle, P middle figure , is uniform about Q, the equant point righthand side figure. Ptolemy combined all three constructions in the models of the planets, Sun, and Moon.

A typical construction might thus be as in the picture below, where E is the Earth, C the geometric center of the eccentric circle, Q the equant point, F the center of the epicycle, and P the planet.

As mentioned before, the eccentric was often not fixed but moved in a circle about the Earth or another point between the Earth and the equant point. Typical Ptolemaic planetary model From Michael J. The idea was to break down the complex observed planetary motion into components with perfect circular motions.

In doing so, however, Ptolemy violated the cosmological and physical rules of Aristotle. The excentric and epicycle meant that planetary motions were not exactly centered on the Earth, the center of the cosmos.

This was, however, a "fudge" that few objected to. The equant violated the stricture of perfect circular motion, and this violation bothered thinkers a good deal more. Thus, in De Revolutionibus see Copernican System , Copernicus tells the reader that it was his aim to rid the models of heavenly motions of this monstrous construction.

Aristotelian cosmology and Ptolemaic astronomy entered the West, in the twelfth and thirteenth centuries, as distinct textual traditions. The former in Aristotle's Physics and On the Heavens and the many commentaries on these works; the latter in the Almagest and the technical astronomical literature that had grown around it, especially the work of Islamic astronomers working in the Ptolemaic paradigm. In the world of learning in the Christian West settled in the universities founded around CE , Aristotle's cosmology figured in all questions concerned with the nature of the universe and impinged on many philosophical and theological questions.

Ptolemy's astronomy was taught as part of the undergraduate mathematical curriculum only and impinged only on technical questions of calendrics, positional predictions, and astrology.