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The Ptolemy/Copernicus/Tycho EJS Model illustrates the relationships between the systems of planetary astronomy developed by Claudius Ptolemy, Nicholas Copernicus, and Tycho Brahe. The model presents a simplified version of all three systems, showing the motions of the Sun/Earth and two planets (one inferior, one superior). The model is initially set to model the planets Venus and Mars. In addition, the apparent motion of the sun and two planets across the sky is displayed in another window.
This model can be used to illustrate the essential geometric equivalence between these three system. In particular, it shows that the Earth's orbit (in the Copernican system) becomes the orbit of the sun in the Ptolemaic and Tychonic systems, and also appears as the deferent of Venus and epicycle of Mars in the Ptolemaic system. The orbit of Venus about the sun (in the Copernican and Tychonic systems) becomes the epicycle of Venus in the Ptolemaic system. The orbit of Mars about the sun (in the Copernican and Tychonic systems) becomes the deferent of Mars in the Ptolemaic system.
Please note that this resource requires
at least version 1.5 of Java (JRE).
Activity for the Ptolemy Copernicus Tycho Model
This zip archive contains LaTeX and PDF versions of a handout for an activity that allows students to explore the Ptolemy Copernicus Tycho Model. The activity focuses on the general geometrical equivalence of the three models, as well as the specific connections between the different models. download 86kb .zip
Published: January 4, 2013
Ptolemy Copernicus Tycho Source Code
The source code zip archive contains an XML representation of the EJS Ptolemy/Copernicus/Tycho Model. Unzip this archive in your EJS workspace to compile and run this model using EJS. download 155kb .zip
Published: May 12, 2011
Rights: This material is released under the GNU General Public License Version 3.
Timberlake, T. (2011). Ptolemy/Copernicus/Tycho Model (Version 1.0) [Computer software]. Retrieved September 29, 2023, from https://www.compadre.org/Repository/document/ServeFile.cfm?ID=11200&DocID=2242
%0 Computer Program %A Timberlake, Todd %D May 12, 2011 %T Ptolemy/Copernicus/Tycho Model %7 1.0 %8 May 12, 2011 %U https://www.compadre.org/Repository/document/ServeFile.cfm?ID=11200&DocID=2242
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