पृष्ठम्:महाभास्करीयम्.djvu/२२८

TRUE LONGITUDE OF MARS, ETC., BY ECCENTRIC THEORY true-mean longitude longitude of planet's apogee + (180°-spasta-bhuja). Similarly, when the mean planet is in the third anomalistic quadrant, true-mean longitude = iongitude of the planet's apogee + (180° + spasta-bhuja); and when the mean planet is in the fourth anomalistic quadrant true-mean longitude = longitude of the planet's apogee +(360° spasta-bhuja). The spasta bhuja is obtained by the the following formula as in the case of the Sun: Rsin (spasta-bhuja SU)= MA X ES ET Rsin x R H where in the bahu or bhuja (due to the planet's mandakendra), R is the radius, and H the planet's distance ET' which is called mandakarna and determined by the method of successive approximations as in the case of the Sun. (See stanza 55) When the true-mean planet is in the first quadrant beginning with V and measu- red in the clockwise direction as shown in the figure, Now consider Fig. 17. The circle VSU, centred at E, is the con- cyclic, V is the sighrocca, and S is the true-mean planet. The circle centred at C, is the fighra eccentric. The point T, where the line through S drawn parallel to EV meets the eccentric, is the true planet. R is the point where ET intersects the concyclic. Tis the first point of Aries. true longitude=arcTSR=arcSv - arc VR D B V R longitude of the sighrocca-spasta-bhuja. 143 T S G Fig. 17 U