A beginner's star-book; an easy guide to the stars and to the astronomical uses of the opera-glass, the field-glass and the telescope (1912)
Murphy, Edgar Gardner, 1869-1913 · New York, London, G.P. Putnam's sons · leaf 131
to confine his obser-vation to double stars in which the compo-nents are rather widely placed and so brightas to make a knowledge of the position angleunnecessary. To some minds the understand-ing of position angle measures is very easy; toothers it is difficult. The chief point to beremembered is… … POSITION ANGLE OF DOUBLE STAR As shoivti in AstronomtcaL Telescope, Image Inverted The angle is reckoned from north {below) at zero; through east (.00°); and south, 180°; round through 2-0, west; to completion of circle at 360° First, let us assume that the angle is measuredwhen the star, as we…
Astronomy
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