On the Revolutions of the Celestial Spheres

13. On the rising and setting of the stars.
14. On investigating the locations of the stars, and the canonical description of the fixed stars. By "canonical," Copernicus refers to the standardized mathematical tables used to track celestial positions.

BOOK THREE.

1. On the anticipation of the equinoxes and solstices. This phenomenon is now known as the precession of the equinoxes, where the positions of the equinoxes slowly shift over time.
2. History of observations proving the unequal precession of the equinoxes and turnings. Copernicus uses "turnings" to refer to the solstices.
3. Hypotheses by which the change of the equinoxes, the obliquity of the zodiac original: "signiferi"; the "sign-bearer," or the path of the sun, and the equinoctial is demonstrated.
4. How reciprocal motion, or oscillation original: "librationis", is composed of circular motions.
5. Demonstration of the inequality of the anticipating equinoxes and the obliquity.
6. On the uniform motions of the precession of the equinoxes and the inclination of the zodiac.
7. What the maximum difference is between the uniform and apparent precession of the equinoxes.
8. On the particular differences of these motions, and their canonical explanation.
9. On the examination and correction of those things set forth concerning the precession of the equinoxes.
10. What the maximum difference is between the intersections of the equinoctial and the zodiac.
11. On establishing the positions of the uniform motions of the equinoxes and the anomaly. In astronomy, an "anomaly" is an angle used to determine the position of a body moving in an orbit.
12. On the calculation of the precession of the spring equinox and the obliquity.
13. On the magnitude and variation of the solar year.
14. On the uniform and mean motions of the revolutions of the earth's center.
15. Preliminary theorems for demonstrating the inequality of the apparent solar motion.
16. On the apparent inequality of the Sun.
17. Demonstration of the first and annual solar inequality, with its particular differences.
18. On the examination of uniform motion in longitude.
19. On establishing the positions and starting points for the uniform motion of the Sun.
20. On the second and twofold variation which occurs regarding the Sun because of the change of the apsides. The apsides are the points in an orbit where a celestial body is either closest to or farthest from the center of its motion.
21. How great the second variation of the solar inequality is.
22. How the uniform motion of the solar apogee The point in the orbit farthest from the Earth. is explained together with the variation.
23. On the correction of the Sun's anomaly and establishing its positions.
24. Canonical explanation of the differences between uniformity and appearance.
25. On the calculation of the Sun's appearance.
26. On the Nychthemeron original: "Νυχθημέρῳ"; a Greek term for a natural day, a full 24-hour period of day and night, that is, the variation of the natural day.

BOOK FOUR.

1. Hypotheses of the lunar circles according to the opinion of the ancients.
2. On the defect of those assumptions.
3. Another opinion concerning the motion of the Moon.
4. On the revolutions of the Moon and its particular motions.
5. Demonstration of the first inequality of the Moon, which occurs at the new and full moon.