On the Revolutions of the Celestial Spheres

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11. 11. On three other acronychal risings of Jupiter observed more recently. An "acronychal" rising occurs when a planet rises in the east just as the sun sets in the west, placing the planet in opposition to the sun and making it visible all night.
12. 12. Proof of the uniform motion of Jupiter.
13. 13. Establishing the positions of Jupiter's motion.
14. y 14. On perceiving the parallaxes of Jupiter, and its height in relation to the orbit of the Earth's revolution. Parallax (referred to here as "commutations") is the apparent shift of a celestial body's position when viewed from different points in Earth's orbit.
15. 15. On the star Mars.
16. 16. On three other late-night brilliance [acronychal risings] of the star Mars observed recently.
17. 17. Proof of the motion of Mars.
18. 18. Determining the positions of Mars.
19. 19. How large the orbit of Mars is in parts, of which the annual orbit of the Earth is one.
20. 20. On the star Venus.
21. What the ratio is between the diameters of the orbits of the Earth and Venus.
22. On the dual motion of Venus.
23. On examining the motion of Venus.
24. On the positions of the anomaly of Venus. In this context, "anomaly" refers to the angular distance of a planet from its furthest point from the center of its orbit.
25. On Mercury.
26. On the position of the highest and lowest apsides of Mercury. The "apsides" are the points in an orbit closest to (perigee) or furthest from (apogee) the center of motion.
27. How great the eccentricity of Mercury is, and what symmetry of orbits it possesses. Eccentricity measures how much an orbit deviates from a perfect circle.
28. Why the elongations of Mercury appear greater around the side of a hexagon than those which occur at perigee. Copernicus is discussing Mercury's complex apparent path as seen from Earth, which does not follow a simple circle.
29. Examination of the mean motion of Mercury.
30. On more recent observations of Mercury's motions.
31. On establishing the positions of Mercury.
32. On another method of approach and withdrawal. This refers to "libration," a perceived oscillating motion.
33. On the tables of prosthaphaereses of the five wandering stars. Prosthaphaeresis is a mathematical correction used to calculate the "true" position of a planet from its "mean" (average) position.
34. How the positions of these five stars are calculated in longitude.
35. On the stations and retrogradations of the five wandering stars. A "station" is when a planet appears to stop moving against the background stars; "retrogradation" is when it appears to move backward.
36. How the times, places, and arcs of the retrogradations are determined.

BOOK SIX.

1. General exposition on the deviation in latitude of the five wandering stars. The "five wandering stars" are the planets known to the ancient world: Saturn, Jupiter, Mars, Venus, and Mercury.
2. Hypotheses of the circles by which these stars are carried in latitude.
3. How great the inclination of the orbits of Saturn, Jupiter, and Mars is.
4. On explaining any other latitudes, and those in general, for these three stars.
5. On the latitudes of Venus and Mercury.
6. On the second transition in latitude of Venus and Mercury according to the obliquity of their orbits at apogee and perigee.
7. What the angles of obliquity are for both stars, Venus and Mercury.
8. On the third type of latitude for Venus and Mercury, which they call Deviation.
9. 9. On the calculation of the latitudes of the five wandering stars.

[OF THE WORK BY] NICOLAUS [COPERNICUS]