On the Revolutions of the Heavenly Spheres

13. On the rising and setting of the stars.
14. On investigating the positions of the stars, and the canonical description of the fixed stars. Copernicus includes a star catalog at the end of Book Two, based largely on Ptolemy's data but adjusted for the precession of the equinoxes.

BOOK THREE.

1. On the anticipation of the equinoxes and solstices. This refers to "precession," the slow change in the orientation of the Earth's axis.
2. History of the observations proving the unequal precession of the equinoxes and their turnings.
3. Hypotheses by which the change of the equinoxes, the obliquity of the zodiac original: signiferi, the "sign-bearer" or ecliptic path, and the equator original: aequinoctialis are demonstrated.
4. How reciprocal motion, or libration a back-and-forth oscillating motion, 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 exposition mathematical tables used for calculation.
9. On the examination and correction of those things set forth concerning the precession of the equinoxes.
10. What the maximum difference of the intersections of the equator and the zodiac is.
11. On establishing the positions of the uniform motions of the equinoxes and the anomaly the angular distance of a planet from its furthest point from the center of motion.
12. On the computation of the precession of the vernal equinox and the obliquity.
13. On the magnitude and difference of the solar year.
14. On the uniform and mean motions of the revolutions of the center of the earth.
15. Introductory 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 according to longitude.
19. On the positions and starting points to be established for the uniform motion of the Sun.
20. On the second and twofold difference which occurs regarding the Sun because of the change of the apsides the points in an orbit closest to and farthest from the center.
21. How great the second difference of the solar inequality is.
22. How the uniform motion of the solar apogee the point where the Sun is furthest from Earth is explained along with its difference.
23. On the correction of the Sun's anomaly and the establishing of its positions.
24. Canonical exposition of the differences between uniform and apparent motion.
25. On the computation of the Sun's appearance.
26. On the Nychthemeron original Greek: Νυχθημέρῳ, that is, the difference of the natural day. A "Nychthemeron" is the full 24-hour cycle of day and night.

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 on 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 moons.