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

VIII.18 VIII. ROMAKA-SIDDHĀNTA — SOLAR ECLIPSE 195 = rā. 6-6-33. Sine rā. 6-6-33 = Sin 6° 33′ = 13′ 41″. The latitude = 13′ 41″ × 7/3 = 31′.9, south, (the Moon being more than 6 rāśis distant from Head of Rāhu). Parallax-corrected latitude = (by verse 14), 31′.9 − 10′.6 = 21′.3, south. Sum of true semi-diameters (by verse 15) : True diameter of Sun = 30′ × 57 ÷ 59 = 29′. True diameter of Moon = 34′ × 835 ÷ 791 = 35′.9. Sum of semi-diameters = (29′ + 35′.9)/2 = 32′.4. Duration (by verse 16): Minutes of arc of duration = 2 × √(32.4² − 21.3²) = 2 × 24′.4 = 48′.8. Time of duration = 48′.8 × 60 ÷ 778′ = nā. 3-46. Half duration = nā. 1-53. Subtracting this from parallax-corrected new moon, first contact is, nā. 20-53 − nā. 19-0, after sunrise. Adding to parallax-corrected new moon, last contact is, nā. 20-53 + nā. 1-53 = nā. 22-46, after sunrise. Part obscured in digits (by verse 17): sum of semi-diameters − parallax-corrected latitude = 32.4 − 21.3 = 11.1. Graphical representation of obscuration S = centre of the Sun M = centre of the Moon SM = parallax-corrected latitude AB = the measure of the obscuration = 1′′.11 = 11.1 digits. Fig. VIII. 1 In this work, I.8-10 give the ‘days from epoch’ according to the Romaka; I.15, gives the elements concerning the Sun and Moon in the Romaka-yuga; VIII.1-8 give the true Sun, Moon and Rāhu; and VIII.9-18 give the solar eclipse according to the Romaka. It is the ‘days of epoch’ of Romaka that is intended to be used everywhere in the work; since it is the distance between two points of time and therefore the same by whatever siddhānta it is computed. The difference caused by the time of the day like ‘Sunset of Ujjain’, ‘Noon at Ujjain’ etc. will, of course, be there, and must be taken into account. The agreement between I.8-10, I.15, and VIII.1-7, each to each, has been shown in the proper places. We have also shown that the Sun, Moon and Rāhu of the Romaka are tropical, though the author has not mentioned this specifically. The work being a manual, intended to be used not for a long period, the difference caused by precession is neglected, no reference being made to it. The periods being tropical, itself indicates that this Siddhānta is foreign. The Sun’s