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Triangles in the Sky: Trigonometry and Early Theories of Planetary Motion
Bibliography and Further Reading
Good accounts of early astronomy can be found in , , and ;  and  also contain sections on early trigonometry. Presentations of the history of astronomy and trigonometry within the more general context of the history of mathematics can be found in  and . For discussions of early astronomy focusing mainly on planetary models and the Copernican Revolution, see  and . The various websites listed below offer Java animations of many of the geometric models of early astronomy, as well as general information pertaining to the subject. The primary source for Greek astronomy and trigonometry is Ptolemy’s Almagest;  is a good English translation. Finally, it should be mentioned that  contains classroom resource materials utilizing various ideas from the history of trigonometry and astronomy.
1. Scott R. Anderson, “Introduction to Astronomy, Lecture 5: The Motion of the Planets,” Open Course, http://www.opencourse.info/astronomy/introduction/05.motion_planets/index.html, accessed September 5, 2008.
4. Dennis Duke, “Ancient Planetary Model Animations,” http://people.scs.fsu.edu/~dduke/models.htm, accessed September 5, 2008.
6. Andres Vargas Idrobo, “Ptolemy’s Theory of Superior Planets,” http://faculty-staff.ou.edu/B/Peter.Barker-1/HSCI3013/planet.html, accessed September 5, 2008.
9. Rosemary Kennett, “Epicycles and Deferents,” http://www.phy.syr.edu/courses/java/demos/kennett/Epicycle/Epicycle.html, accessed September 5, 2008.
12. Craig Sean McConnell, “Models of Planetary Motion from Antiquity to the Renaissance,” http://faculty.fullerton.edu/cmcconnell/Planets.html, accessed September 5, 2008.
15. Scott C. Smith, “Retrograde Motion,” http://www.lasalle.edu/~smithsc/Astronomy/retrograd.html, accessed September 5, 2008.
16. “Ptolemaic System Generator,” Nebraska Astronomy Applet Project, http://astro.unl.edu/naap/ssm/animations/ptolemaic.swf, accessed September 5, 2008.
17. “Ptolemy’s Epicycle,” http://www.sciences.univ-nantes.fr/physique/perso/cortial/bibliohtml/epiclc_ja.html, accessed September 5, 2008.
21. Greg Van Brummelen, “Animations of Ptolemy’s Planetary Models,” http://faculty.bennington.edu/~gvanbrum/, accessed September 5, 2008.
Caravella, Sandra M., "Triangles in the Sky: Trigonometry and Early Theories of Planetary Motion," Loci (October 2008), DOI: 10.4169/loci003120
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