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| Subjects | Page Numbers |
|---|---|
| 14. Calculation of the Precession of Equinoxes original: "अयनांश"; the slow shift of the orientation of Earth's axis, essential for aligning solar and sidereal calendars | 28 |
| 15. Difference in Rising Times original: "उदयान्तरं"; similar to the modern 'Equation of Time,' correcting for the Sun's irregular motion | 29 |
| 16. Ascensional Difference original: "चरकर्म"; a correction for the observer's latitude to determine the length of day and night | 30 |
| 17. Calculation of Lunar Days, Half-Days, Asterisms, and Junctions original: "तिथि-करण-नक्षत्र-योग"; the five elements of the traditional Hindu calendar (Panchangam) | 31 |
| 1. Calculating Local Rising Times and the Ascendant original: "लग्न"; the point of the zodiac rising on the eastern horizon at a specific time | 35 |
| 2. Finding the Elapsed Time from the Ascendant | 36 |
| 3. Calculating Zenith Distance and the Hour Angle original: "नतोन्नत"; terms describing the position of a celestial body relative to its highest point (zenith) | 38 |
| 4. Calculating Shadow Length from Time and Time from Shadow Length | 39 |
| 5. Finding Declination using the Gnomon original: "क्रान्तिदण्ड"; a vertical rod used to measure shadows for astronomical calculations | 43 |
| 6. Alternative Method for Calculating Declination | 44 |
| 7. Calculating Local Latitude original: "अक्षांश"; the distance of the observer north or south of the equator | 45 |
| 1. Calculating the Zenith Distance | 48 |
| 2. Calculating Instantaneous Planetary Positions | 50 |
| 3. Calculation of Celestial Latitude original: "शर"; literally 'arrow,' referring to the angular distance of a planet north or south of the ecliptic | 51 |
| 4. Knowledge of Precession and an Alternative Calculation for Latitude | 51 |
| 5. Calculating the Diameters of the Moon and the Earth’s Shadow | 52 |
| 6. Calculating the Magnitude of Obscuration original: "ग्रासमान"; the extent to which the celestial body is covered during an eclipse | 53 |
| 7. Calculating the Duration of the Eclipse and Total Obscuration | 54 |
| 8. Calculating the Five Key Times of an Eclipse beginning, start of totality, middle, end of totality, and final contact | 54 |
| 9. Calculation of the Deflection original: "वलन"; the angle used to orient the eclipse diagram correctly against the horizon | 56 |
| 10. Calculating Latitude at the Moments of Contact and Separation | 59 |
| 11. Description of Graphical Projection original: "परिलेख"; the method of drawing a diagram to visualize the eclipse's path | 60 |
| 12. Identifying the Points of Contact, Middle, and Separation | 61 |
| 13. Calculating Obscuration at any Desired Time | 61 |
| 1. The Nature of Zenith Distance and Hour Angle | 64 |
| 2. Calculating Parallax in Longitude and Latitude original: "लम्बन" and "नति"; corrections needed for solar eclipses because the observer is not at the Earth's center | 65 |
| 3. Alternative Method for Calculating Parallax | 67 |
| Subjects | Page Numbers |
|---|---|
| 4. Calculating the Duration and Other Phases | 68 |
| 5. Calculating the Moments of Contact and Separation | 69 |
| 6. The Colors of the Sun and Moon during an Eclipse | 73 |
| 1. Calculating the Rising and Setting of Jupiter | 75 |
| 2. Calculating the Rising and Setting of Venus | 78 |
| 3. Calculating Retrograde Motion from the Anomaly | 80 |
| 4. Rising and Setting Times for Mars, Jupiter, and Saturn | 80 |
| 5. Knowledge of the Rising and Setting of Mercury and Venus | 81 |
| 6. Calculating the Duration of Retrograde Motion and Other Phases | 81 |
| 7. Time-Degrees, Nodes, and Latitudinal Deflections of Planets | 82 |
| 8. Description and Calculation of Planetary Latitudes | 83 |
| 9. Visibility Corrections and Rising/Setting Calculations | 83 |
| 10. Special Instructions and Exceptions | 85 |
| 11. The Rising and Setting of the Star Canopus original: "अगस्त्य"; an important star for navigation and calendar-keeping in India | 86 |
| 1. Calculation of the Deflection | 90 |
| 2. Description of the Bright and Dark Portions of the Moon | 91 |
| 3. Description of the Graphical Projection of the Lunar Crescent | 91 |
| 1. Calculating the Angular Diameters of Mars and Other Planets | 95 |
| 2. Knowledge of the Time of Conjunction | 96 |
| 3. Calculation of the Conjunction original: "युति"; the moment when two celestial bodies appear close together in the sky | 96 |
| 1. Possibility of a Special Conjunction and Past/Future Events original: "पात"; specifically referring to the rare and inauspicious times when the Sun and Moon have equal declinations | 103 |
| 2. Knowledge of the Motion and Future Occurrence of the Conjunction | 103 |
| 3. Positive and Negative Values of Declination Segments | 104 |
| 4. Calculating the Elapsed Segments | 105 |
| 5. Calculating Past and Future Occurrences of the Conjunction | 105 |
This concludes the general Table of Contents for the mathematical sections of the text.