The American Ephemeris and Nautical Almanac

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Page 560 - In the year 1887 there will be four eclipses, two of the Sun and two of the Moon. I. — A Partial Eclipse of the Moon, February 7-8, visible at Washington and also in the Pacific Ocean and part of Asia.
Page 686 - Sidereal Time. — Sidereal time is measured by the daily motion of the stars; or, as it is used by astronomers, by the daily motion of that point in the equator from which the true right ascension of the stars is counted.
Page 685 - Solar time is that used for all the purposes of ordinary life, and is measured by the daily motion of the sun. 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 696 - In case they would have differed, the minute which would have been numerically larger is diminished by one, and the seconds increased by sixty, so that there is always a correspondence between the two numbers. The hourly motions in right ascension and declination are given for the moment of mean noon, but may be regarded as having the same values for apparent noon. The Equation of Time for Apparent Noon is the correction to be applied to apparent time in order to obtain mean time. It is, therefore,...
Page iii - Greenwich, gives the ephemerides of the sun and moon, the geocentric and heliocentric positions of the major planets, the sun's coordinates, and other fundamental astronomical data for equidistant intervals of Greenwich mean time ; Part II, Ephemeris for the meridian of Washington gives the ephemerides of the fixed stars, sun, moon, and major planets for transit over the meridian of Washington ; and Part III, Phenomena, contains predictions of phenomena to be observed with data for their computation.
Page 686 - The civil day begins twelve hours before the astronomical day; therefore the first half of the civil day corresponds to the last half of the preceding astronomical day, and the last half of the civil day coincides with the first half of the astronomical day of the same date. Thus, January 9, 2 o'clock, AM, civil time, is January 8, 14'', astronomical time; and January 9, 2 o'clock, PM, civil time, is also January 9, 2h, astronomical time.
Page 694 - The sidereal time for which any set of quantities is given can be found by interpolation from these numbers. The following is an example of the reduction of a star to apparent place by the Besselian star-numbers : — Computation of the apparent place, of v Aquarii for iScq, August /7, for the upper transit at Washington.
Page 75 - NOTE.- -The semidiameter for mean noon may be assumed the same as that for apparent noon.
Page xvi - Conjunction, or having the same Longitude or Right Ascension. D Quadrature, or differing ±90° in Longitude or Right Ascension.
Page 706 - H — \, taken without regard to sign, must be less than the semi-diurnal arc of the star by at least one hour. On very rare occasions an emersion might be seen in the east horizon, or an immersion in the west, when this difference is a few minutes less than an hour. 3. The sun must not be much more than an hour above the horizon at the local mean time T — Л, unless the star is bright enough to be seen in the day time.

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