8A30.30 - Retrograde Motion of Inner Planets Demo

Code Number:
Demo Title:
Retrograde Motion of Inner Planets Demo
Retrograde Motion of Inner Planets
Area of Study:
Solar System
Retrograde Demo, VHS Tape - Retrograde Motion - Geocentric Model, VHS Tape - Retrograde Motion - Heliocentric Model.

No preparation needed beyond regular maintenance to insure tightness of set screws, etc. Works best to hang this on the Blackboard Optics board.

  • Herman Erlichson,  "The Retrograde Motion of Mars",  TPT, Vol. 37, # 6, p. 342, Sept. 1999.
  • Matthew J. Moelter and Bernard A. Bates, "Hands-On Epicycles and Retrograde Motion", TPT, Vol. 35, # 9, p. 554-555, Dec. 1997.
  • Herbert T. Wood, "Retrograde Motion - An Out-of-Doors Lab", TPT, Vol. 30, # 5, May 1992, p. 302.
  • A.S. Biffi, "Understanding the Retrograde Motion of a Planet",  TPT, Vol. 21, # 4, Apr. 1983, p. 252.
  • Ronald Lane Reese, "Comment on 'A Retrograde Motion Demonstration Model' [Am. J. Phys. 54, 1021 (1986)]", AJP, Vol. 55, #5, May 1987, p. 393.
  • Albert Ackroyd, Hendrik J. Gerritsen, "Retrograde Motion Demonstration Model", AJP, Vol. 54, # 11, Nov. 1986, p. 1021.
  • Edward Kimmer, "Alternate Diagram of Retrograde Motion", AJP, Vol. 43, # 7, July 1975, p. 639.
  • Hugo N. Swenson, "The Homocentric Spheres of Eudoxus", AJP, Vol. 31, #6, June 1963, p. 456.
  • Janice VanCleave,  "13, Back Up",  Astronomy for Every Kid - 101 Easy Experiments That Really Work, p. 30.
  • Isaac Asimov,  "Smashing the Sky",  Fantasy & Science Fiction Magazine, pp. 132.
  • # 37, "Back and Forth", Janice VanCleave's 203 Icy, Freezing, Frosty, Cool, and Wild Experiments.
  • 4.14, "Direct and Retrograde Motion of the Planets", Project & Demonstrations in Astronomy by D. Tattersfield, p.70.

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