AKSA-DRKKARMA drawn through M' intersects the ecliptic¹, and T the point where the horizon intersects the ecliptic. Then the arc MT of the ecliptic denotes the total visi- bility-correction; the arc ML denotes the visibility correction due to ecliptic-deviation (ayana-dṛkkarma); and the arc LT denotes the visibility correction due to the latitude of the local place (akṣa- dṛkkarma). The visi- bility-correction for a planet is defined in the same manner. - S E Z = T Fig. 21 The correction stated in the above stanzas is the akşa-dṛkkarma for the Moon. The formula stated is Rsin x Moon's latitude Rcos p akṣa-dṛkkarma where is the latitude of the local place. This formula is approximate. Let A be the point where the diurnal circle through M intersects the hour circle through M', B the point where the diurnal circle through M intersects the horizon, and C the point where the hour circle through B intersects the diurnal circle through M'. Then proceeding as for finding the earthsine, it can be easily shown that arc CM' Rsin x Rsin (arc BC) Rcos Rsin x Moon's latitude Rcos 183 approx.
- T is called dig-graha. See ŚiDV, I, vii. 4.
approx. ¹ The point L is called ayana-graha or ayana-graha. See ŚiDVṛ, 1. vii. 2,4.
