The American Ephemeris and Nautical Almanac

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Page 409 - In the year 1896 there will be four eclipses, two of the Sun and two of the Moon.
Page 508 - Star, viewed with a telescope that inverts, will disappear and reappear. By "Angle from N. Point" is to be understood the arc included between the Star, when in contact, and the point of intersection of the limb with a circle passing through the North Pole and the centre of the Moon's image ; and by "Angle from Vertex...
Page 497 - ... velocity. This mean sun is supposed to keep, on the average, as near the real sun as is consistent with perfect uniformity of motion; it is sometimes in advance of it, and sometimes behind it, the greatest deviation being about 16 minutes of time.
Page 497 - A Solar Day is the interval of time between two successive transits of the sun over the same meridian; and the hour-angle of the sun is called Solar Time.
Page 497 - ... of the sun is called Solar Time. This is the most natural and direct measure of time. But the intervals between the successive returns of the sun to the same meridian are not exactly equal, owing to the varying motion of the earth around the sun, and to the obliquity of the ecliptic.
Page 497 - ... ascension of the stars is counted. This point is the vernal equinox, and its hour-angle is called Sidereal Time. Astronomical clocks, regulated to sidereal time, are called sidereal clocks. A Sidereal Day is the interval of time between the transit of the vernal equinox over...
Page 505 - If the instant for computation were correctly chosen at the time of beginning or end of the eclipse, m would be exactly equal to a. If m is not equal to a, the instant for a new computation, and which will be an approximation to the actual time of beginning, may be found by adding to the preceding time of computation an interval /. which may be obtained in seconds by the formulae log. ,u'=1.8G167 log. Я'= 1.3757 tan.iy=s=f а'=Л

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