पञ्चसिद्धान्तिका (आचार्य वराहमिहिर - सूर्य, रोमक, पौलिश, वासिष्ठ एवं पितामह सिद्धान्त)

60 PAÑCASIDDHĀNTIKĀ III.20 is the Mahāvyatīpāta, distinct from the seventeenth of the Viṣkambha series, which is not what we are talking about here.) Prabhākara, generally mentioned as a disciple of Āryabhaṭa, has mentioned seven yogas, which he called Mahādoṣaḥ ('the great Inauspicious'). This information we have from two ślokas quoted by Śaṅkaranārāyaṇa in his commentary on the Laghubhāskarīya as Prabhakāra's. The ślokas say, "Find Sun plus Moon, in terms of nakṣatra-segments. When they are equal to twenty-seven (i.e. a full revolution), when 14, 8, 12, 5, 17, 18 and 10 are added, there are the Mahādoṣas Nirodha, Parigha, Vajra, Daṇḍa, Gaṇḍa Śūla and Vyatīpāla, respectively. In this group, all excepting Daṇḍa, can be identified in the Viṣkambha series. Prabhākara has not included Vaidhṛta in the group, perhaps because he does not consider it as a Mahādoṣa. Because these are computed individually, by a special rule, we can conclude that the twenty-seven yogas, Viṣkambha etc., were not in vogue in the days of Prabhākara. We have mentioned that in the days of Bhāskara a senior contemporary of Brahmagupta, also the twenty-seven yogas did not exist. Though it may be supposed that the twenty-seven yogas had come into vogue by Brahmagupta's days from the statement, "The minutes of the sum of the longitudes of the Sun and the Moon, divided by 800 are the yogas", (Br. SpSi., Spaṣṭa. 63) and on the strength of this we ourselves have written that Brahmagupta knew the twenty-seven yogas, in our Introduction to the Mahābhāskarīya, it is now learnt that the statement is an interpolation because this is not taken up and commented upon by Pṛthūdakasvāmi in his Bhāṣya of the Brāhmasphuṭa-Siddhānta and also because in giving the computation of puṇyakālas at the ends of tithis, nakṣatras, etc. according to custom, like Vaṭeśvara and Śrīpati, Brahmagupta omits yoga while the others include yoga as well. In the Sūrya-Siddhānta etc. which are later, the Viṣkambha series find a place. Thus of the five aṅgas, the yoga was the last to develop. We said that the Vyatīpāta was the first yoga born and next Vaidhṛta. We shall consider their nature and how they arose. The Vedic priests and astronomers were in the habit of observing the sky looking for celestial occurrences like the rising and setting of the Sun and the Moon, because of the need of this kind of knowledge for the performance of yajñas and out of thirst for knowledge. It is said that the Gavām-ayana Satra was designed for this very purpose. The following facts were observed by them. At one time the Sun rises farthest south of the East point, that is the end of Dakṣiṇāyana and beginning of Uttarāyaṇa. (This is the winter solstice). After that, the Sun rises more and more north every day and, at the end of six months, rises farthest north. Then is the end of Uttarāyaṇa and the beginning of Dakṣiṇāyana. (This is the summer solstice). From that time it begins to rise more and more to the south, until after six months again it is farthest south. This is the end of Dakṣiṇāyana and the beginning of Uttarāyaṇa again. Thus in a year there are the two courses of the Sun, northward and southward. In a given place, the exact point north or south where the Sun rises depends on its declination north or south. Like the Sun, the Moon too, according to its declination, rises north or south of the east-point and has its Uttarāyaṇa in about fourteen days and its Dakṣiṇāyana in about the same period, the total taking a little more than twenty-seven days. Now, the day on which the Sun and the Moon rise almost at the point, one moving south-ward, and the other moving north-ward, coming to meet each other as it were, that day is the Vyatīpāta. Because they cross each other moving in different directions, the phenomenon is called Vyatīpāta or Vyatipāta. Now, how can the time of the phenomenon be computed? Because they must rise nearly at the same point, their declinations must be nearly equal. That they must be moving in opposite directions, i.e. their respective ayanas should be different, has been mentioned. These two conditions can be approximately secured if the position of one is as far away on one side of the junction of Uttarāyaṇa and Dakṣiṇāyana, as that of the other is on the other side of the junction. Let us take it that the