पृष्ठम्:लघुभास्करीयम्.djvu/१५७

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84 Suppose that a planet is rising on the eastern horizon or setting on the western horizon. Then the portion of the ecliptic lying between the hour circle of the planet and the horizon is defined as the al:$0-alau of the planet; and the portion of the ecliptic lying between the hour circle and the circle of longitude is defined as the gy070-0alu0 of the planet. The true longitude of a planet calculated in accordance with the rules stated in chapter II above denotes the longitude of that point of the cliptic where the planet's circle of longitude meets it. The object of the visibility corrections is to obtain the longitude of that point of the ecliptic which rises or sets with the planet. This has been done in two steps by the successive application of the nksa- and gy५070- dkarmas. The natural order, however, is to apply the gyna-dkarma first and.the aka-dkarाma next. Generally this matural order of correction has been followed by the Hindu astronomers The formulae for the alk०- and gyana- dkarmas for the Moon stated in the text are : 0rm's latitude) ................ , ९sin xR in ( Rversirm (14-90°) x Rsin 6 x Moon's latitude where M is the Moon's (tropical) longitude, 2 the latitude of the place, and 6 the Sun's greatest declimation. e rationale and discussion of these formulae, the reader is refered t my notes on MBh, wi. 1-3 Minimum distance of the Moon from the Sun, in terms of deg rees of time, at which she becomes visible : 5. When the Moon obtained by applying these (two visi bility) corrections is found to be twelve degrees (of time) distant from the Sun, she shall be (just) visible in clear cloudless sky.१ What the author really means is that : Rversin {{bhuja (M- 90")} x Rsin e x Moon's latitude ( 70 = R* Cf. MB, wi. 4(ii)- 50(i). [While consulting my edition of the MBh, read “time ofsetting' in place of“obligue ascension' in line 21, p. 186, and “set ing” in place of “obligue ascension' in line 31, p. 188. Similarly, the word “agu७” occuring in lines 5 and 7, p. 192, should be changed into “29us of setting' , and that occurring in line 9, p. 192, into “45us of rising”. The last sentence of that paragraph should be deleted]