DIRECT AND RETROGRADE MOTION for (sunrise on) the day elapsed (i.e., yesterday) is the (true) daily motion (of the planet for the day elapsed). Hindu astronomers have recognised eight kinds of motion of the planets. According to the Surya-siddhanta, these are: (1) vakra (begin- ning of regression), (2) ativakra (maximum regression), (3) kutila (end of regression and beginning of direct motion), (4) manda (slow), (5) manda- tara (slower), (6) sama (mean), (7) śighra (fast), and (8) sighratara (faster). Of these, says the author of the Surya-siddhanta, the first three are the different kinds of retrograde motion and the last five the various forms of direct motion. The above stanzas 56 and 57 deal with the three varieties of retrograde motion. The details of the five varieties of direct motion are given by Sripati in his Siddhanta-sekhara.³ According to him, the motion is said to be "very fast", when the planet (measured from its fighrocca) is in the beginning of the sign Aries or Pisces; "fast", when in the beginning of Taurus or Aquarius; "mean" when in the beginning of Gemini or Capricorn; "slow", when in the first half of Cancer or in the last half of Sagittarius; and "very slow", when in the first half of Sagit- tarius or in the last half of Cancer. The following table gives the sighrakendras of the planets when they take up, retrograde motion according to various Hindu authorities: Sighrakendras of the planets when they take up retrograde motion. Sighrakendra Planet Mars Mercury Jupiter Venus Saturn Br SpSi (ii.48), SiDV (Iii. 47), KPT (iii. 8), Sise (iii. 58), Si Si (1, ii. 41) 1630 1450 1250 1650 1130 KKau (ii.23), GLā (iii.15) 163⁰ 1450 1250 . 1670 1130 MSi (iii.31) 1 ii. 12. Susi, ii.13. iii. 60. !~ 147 1630 1450 1250.. 166⁰ 1130 VVSi (ii.30), SuSi (ii.53-54) 1640 1440 130° 1630. 1150 PiSi, KK (iii. 8-17) 1640 1460 1250 1658! 133⁰
