Ball, Robert S. (Robert Stawell), Sir, 1840-1913 · Cambridge, University press · leaf 121
[CH. V 106 RIGHT ASCENSION AND DECLINATION celestial sphere by the sine of the latitude. In the small time dt the star S (Fig. 34) moves over SS' = cos Sdt. If S'T be perpendicular to ZS we have S'T=S'Ssm S'ST=coa 8coa7idt=am<l>dt. Hence S'ZS= sin «/> dt. … Fig. 34. 38. Celestial latitude and longitude. For certain classes of investigation we have to employ yet another system of co- ordinates on the celestial sphere. Just as the equator has furnished the means of defining the right ascension and the declination of a star, so the ecliptic is made the…
Spherical astronomy
Internet Archive · Cornell University Library · Public domain (published before 1931). Free to use for anything.
