सिद्धान्तशिरोमणि: गणिताध्याय (भास्कराचार्य - ग्रहगणित, मध्यमाधिकार व स्पष्टाधिकार सटीक)

221 by Brahmagupta, that Ṛiṣis like Puliśa, Vasiṣṭha and Garga spoke about these Sukṣmanakṣatras. The duration of Abhijit calculated as directed is 254' — 18''. The computation as directed is easy for understanding. The reason for the durations indicated is not clear but is to be taken as based on Astrology. Verses 76, 77. The duration of the planets’ transit into new Rāśis and the duration of the interval between successive stars, tithis, Karaṇas and yogas. The disc of the planet multiplied by 60, and divided by its daily motion gives the nāḍīs of transit of the planet from Rāśi to Rāśi. This duration is considered to be holy for performing Vedic rites. It is the holiest with respect to the Sun’s transit in particular. A planet in its transit gives partly holy results not so much as the Sun, depending upon the nature of the previous and succeeding Rāśis. The duration of Sandhi for tithis is got by dividing the disc of the Moon expressed in seconds by the difference of the daily motions of the Moon and the Sun; so also with respect to Karaṇas. The Sandhi between two Nakṣatras is obtained by the same measure of the disc of the Moon expressed in seconds of arc being divided by the Moon’s daily motion. The Sandhi between two yogas is got by dividing the same numerator by the sum of the daily motions of the Sun and the Moon. Comm. (1) The Sandhi is the period that elapses during the transit of the disc concerned between the Rāśis and nakṣatra divisions. With respect to tithi, Karaṇa and yoga, the divisions are imaginary not being seen in the Sky and the disc concerned is that of the Moon, and not that of the Sun though the Sun’s motion is also taken into account. We say a transit from a division to another is current so long as the disc lies partly in the previous and partly in the latter. So the Sandhi begins when the disc touches the next division and ends when its hind part