132 TRUE LONGITUDE OF A PLANET The first round of the movable karanas begins with the second half of the first tithi in the light half of the month, and the eighth round ends. on the first half of the fourteenth tithi in the dark half of the month. Thus in the light half of the month, the second karana is Bava, the third karana is Bālava, the fourth karana is Kaulava, and so on; and in the dark half of the month, the first karana is Bālava, the second karapa is, Kaulava, and so on. The four immovable karanas occur in succession after the eighth round of the cycle of the seven movable karanas. Calculation of the naksatra: 34. The true longitude of a planet reduced to minutes and then divided by 800 gives the number of nakṣatras passed over (by the planet). From the remainder (multiplied by 60 and) divided by the (planet's true daily) motion are obtained the ghatis elapsed (since the planet's entrance into the current nakṣatra).¹ We have seen that in Hindu astronomy the stars lying near the eclip- tic are divided into 27 groups called naksatras. Beginning with the first point of the nakṣatra Asvini,³ the ecliptic is divided into 27 equal parts, each of 800 minutes (of arc). These divisions of the ecliptic also are called nakṣatra and given the same names as the twenty-seven star-groups, i. e., Aśvini, etc. The nakṣatras referred to in the above stanza are these divi- sions of the ecliptic. Given the longitude of a planet the above rule enables us to de- termine the number of nakṣatras passed over by the planet and the time elapsed since it crossed into the current nakṣatra. The phenomena of vyatipāta: 35-36. When the sum of the (true) longitudes of the Sun and the Moon amounts to half a circle (i.e., 180°), the pheno- ¹ This rule is found also in SüSi, ii. 64; BrSpSi, ii. 61; KK (Sengupta's edition), i. 24; SiDVṛ, I, ii. 23(i); Siśe, iii. 75; SiSi, I, ii. 67. 2 Vide supra, Chapter III, stanzas 62-75(i). 3 The first point of the nakṣatra Aśvini (also called the first point of Aries) is the fixed point from which the longitudes of the planets are measured in Hindu astronomy. This point coincides with the junction-star of the nakṣatra Revati, i.e. with y Piscium.
