ANGULAR DIAMETERS OF SUN, MOON AND SHADOW That is, Sun's diameter in minutes = and Moon's diameter in minutes = Formulae for the true (i.e., angular) diameters of the Sun, the Moon, and the shadow' in terms of the true daily motions of the Sun and the Moon : That is to say, (1) Sun's true diameter 6-7. Five-ninths of the (minutes of the Sun's true) daily motion and one-twenty-fifth of the (minutes of the Moon's true) daily motion (treated as minutes) respectively increased and diminished by the seconds equal to one-fourths of themselves are to be known as the true diameters of the Sun and Moon (respectively). One-tenth of (the minutes of) the moon's true daily motion (treated as minutes) plus one-sixteenth of the same treated as seconds is stated to be the (true) diameter of the shadow.2 = (2) Moon's true diameter Sun's diameter in yojanas x R Sun's true distance in yojanas Moon's diameter in yojanas x R Moon's true distance in yojanas 9 + 5 + 36 (Sun's true daily motion in minutes) seconds; (Sun's true daily motion in minutes) minutes tss (3) True diameter of the shadow Moon's true daily motion in minutes 25 minutes seconds; Moon's true daily motion in minutes 100 Moon's true daily motion in minutes minutes. 10 Moon's true daily motion in minutes 16 seconds. ¹ By the shadow is meant in this chapter the section of the cone of the Earth's shadow at the Moon's distance. 2 Similar rules occur also in Br.Sp.Si, iv. 6(i); KK (Sengupta's edition), iv. 2(i) ; ŚiDVṛ, I, iv. 9; MSi, v. 5(ii); SiŚe, v. 9; Siśi, I, v. 8-9 ; KPr, v. 2.
