THE SO CALLED "DIVIDING NUMBERS" FOR THE PLANETS 203 According to Aryabhata I,' the diameter of the Moon is 315 yojanas, and the diameters of Venus, Jupiter, Mercury, Saturn, and Mars are respec- tively one-fifth, one-tenth, one-fifteenth, one-twentieth, and one-twenty- fifth of the diameter of the Moon (at the Moon's mean distance). It follows that the diameter of a planet in minutes diameter of the planet in yojanas x R Moon's mean distance in yojanas diameter of the planet in yojanas 10 diameter of the Moon in yojanas 10 X D where D = 5, 10, 15, 20, or 25, according as the planet is Venus, Jupiter, Mercury, Saturn, or Mars. 32 D ¹ A, i. 7. approx. approx. approx., Hence the rule in the text. Definition of the "dividing numbers" for the planets : 57 (Severally) multiply the yojanas of the Moon's (mean) distance by the same numbers (i.e., by 5, 10, 15, 20 and 25): the result, in each case, is the "dividing number", in terms of yojanas, used in the determination of the lambana and nati (for the respective planets). The "dividing numbers" denote the mean distances of the planets under the assumption that the diameter of each of them is 315 yojanas (the same as that of the Moon). A rule for finding the true distance of a planet, assuming 315 yojanas for its diameter, in terms of yojanas : 58 (i). These (above-mentioned) "dividing numbers" be- come accurate when multiplied by the "divisor" and divided by the radius.
