Page 23 - GALIET PHYSICS BLOSSOMS I+

Sequences of Figure C.18
On Mercury19
Ptolemy found that the Equant Model worked for all planets, except Mercury. The equant for Mercury could not be stationary!
It had to revolve on a complete separate auxiliary circle:
On the Other Planets20
For Ptolemy, too, the equant points for the other planets were different points in space.
Only two planets are shown:
18 Sequences of Figure C were taken from http://faculty.fullerton.edu/cmcconnell/Planets.html
19 This figure and explanation is drawn from Dr. Robert A. Hatch’s
h t t p : / / w w w . c l a s . u fl . e d u / u s e r s / u fh a t c h / H I S - S C I - S T U D Y - G U I D E / 0 0 3 4 _ s u m m a r y P t o l e m i a c A s t r o n . h t m l 20 This figure and explanation is drawn from Dr. Robert A. Hatch’s
h t t p : / / w w w . c l a s . u fl . e d u / u s e r s / u fh a t c h / H I S - S C I - S T U D Y - G U I D E / 0 0 3 4 _ s u m m a r y P t o l e m i a c A s t r o n . h t m l
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