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| Subjects | Page Numbers |
|---|---|
| 6. Calculating the Mean Node original: "पातमध्यानयनम्"; refers to the calculated average position of the lunar nodes, Rahu and Ketu | 106 |
| 7. Special Remarks | 107 |
| 8. Determining the Duration original: "स्थिति"; often refers to the duration of an astronomical event like an eclipse | 108 |
| 9. Consideration of the Corrected Portions | 108 |
| 10. Determining Duration based on the Node | 109 |
| 11. Equality of Declination and Characteristics of Duration | 109 |
| 1. Calculating Celestial Latitude original: "शरसाधनम्"; the angular distance of a planet north or south of the ecliptic | 115 |
| 2. Calculating Zenith Distance | 116 |
| 3. Possibility and Impossibility of Eclipses | 117 |
| 4. Description of the Author's Lineage | 119 |
| 1. Clarification of the Sun's Position according to the Nirada method | 120 |
| 2. The Purpose of this Method | 120 |
| 1. Section on Mean Motions | 122 |
| 2. Section on True Motions | 125 |
| 3. Section on the Three Problems Time, Direction, and Place | 130 |
| 4. Section on Lunar Eclipses | 132 |
| 5. Section on Solar Eclipses | 136 |
| 6. Section on Heliacal Risings and Settings | 138 |
| 7. Section on the Elevation of the Moon’s Horns The phase and orientation of the crescent moon | 141 |
| 8. Section on Planetary Conjunctions | 142 |
| 9. Section on the Nodes | 143 |
| 10. Section on the Possibility of Syzygy | 145 |
| 11. The Nirada Chapter | 147 |
| 12. Index of Verses | 148 |
The Invocation (Mangalacharana)—
Having bowed to Ganesha, to the Goddess of Speech (Saraswati), to the Creator (Brahma), to the Unchanging (Vishnu), to the Lord (Shiva), and to the Planets beginning with the Sun, I shall describe the concise process of planetary calculation, which is in perfect agreement with the Brahma Siddhanta. ॥ 1 ॥
Sumatiharsha's Introductory Verse:
He who, like a lotus, shines with the beauty of a pond, though immersed in the ocean of the five arrows of love by the splashing water droplets of the mountain rocks; He who is praised by millions of gods possessed of wonderful fortitude; He whose nature and majesty remain the same toward friend and foe—may the glorious Lord Parshva and his beloved protect us. This is a devotional verse to Parshvanatha, the 23rd Tirthankara of Jainism, indicating the commentator Sumatiharsha's religious background.
I, the author named Bhaskara, having bowed to Ganapati, Saraswati, Brahma, Vishnu, Shiva, and the planets starting with the Sun, shall explain the "planetary work"—that is, the method for determining the mean and true positions of the heavenly bodies. To remove any doubt regarding the authority of this work, it is described as being "in agreement with the Brahma Siddhanta." The Brahma Siddhanta is a foundational astronomical text; by claiming alignment with it, Bhaskara assures readers his shortcuts are scientifically valid.
If one wonders why this work is necessary if the meaning is already known from the Brahma Siddhanta, the answer is: this is a "concise process" (laghu-prakriya). By making the process concise, it becomes "perfectly clear," meaning easy to understand. This is the reason for the undertaking.
Now, one might ask, since the primary goal of the Siddhantas is the calculation of planets, what is the specific name and category of this science? In the science of mathematics/astronomy, there are three types: Siddhanta, Tantra, and Karana.
Furthermore, if one asks how a simple bow (invocation) has the power to destroy obstacles, the answer is: through the merit of the bow, obstacles are struck down. Even where a work is seen to be completed without an explicit invocation, it is understood that a mental salutation...