The American Ephemeris and Nautical AlmanacU.S. Government Printing Office, 1906 |
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Common terms and phrases
Aldebaran Antares Antares E Apparent Declination apparent noon APPARENT PLACES Apparent Right Ascension Aquarii Aquilæ Arietis ASCENSION AND DECLINATION Besselian Cancri Ceti CONSTANTS OF STRUVE Day of Month Decl Direction of Object eclipse Ephemeris Fomalhaut Frid Geminorum GREENWICH MEAN NOON h m h m Heliocentric Horizontal Parallax Hour Angle July June JUPITER JUPITER W Latitude Leonis Libræ Logarithm LUNAR DISTANCES MARS Mean Mean Mean Mean Solar Date Meridian Passage Midnight Minute Moon MOON'S RIGHT ASCENSION Name and Direction Ophiuchi P. L. of Diff Parallax Pegasi Piscium Pollux Pollux W Regulus Regulus W Right Declina Sagittarii SATURN SATURN W Scorpii Sept sidereal Solar Solar Solar Spica Spica W STRUVE AND PETERS Sun's Tauri Thur tion Ascension tion North tion sion tion South TRANSIT AT WASHINGTON True Longitude Tues UPPER TRANSIT Virginis 6.5 WASHINGTON MEAN ΙΟ ΙΟΙ
Popular passages
Page 564 - 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 436 - Greenwich mean time of beginning and ending at any place may be found with an uncertainty which will vary from three or four minutes for a high Sun to fifteen or twenty minutes when the Sun is near the horizon.
Page 570 - Passage shows the hour, minute and tenth of that passage of the planet over the meridian of Greenwich which occurs next after the noon of the date. The right ascension and declination of a planet are required whenever it is observed for time, latitude or azimuth. The mode of reducing the ephemeris positions of planets to other instants of Greenwich mean time is the same as that given for the Sun on pages 554 — 555.
Page 436 - In the year 1891 there will be four Eclipses : two of the Sun and two of the Moon. I. A total Eclipse of the Moon, May 23, partly visible at Greenwich as a partial Eclipse.
Page 563 - 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 571 - The heliocentric latitude is counted from the true ecliptic of the date The Logarithm of Radius Vector is the logarithm of the distance of the center of the planet from that of the Sun, at the Greenwich mean noon whose date is given in the first column. The last two columns give, respectively, the logarithm of the true distance of the center of the planet from that of the Earth, for the Greenwich noon indicated on the...
Page 569 - Greenwich mean time, beginning at noon; the dates are therefore astronomical. All the distances that can be observed on the same day, are grouped together under that date; and the columns are read from left to right, across both pages of the same opening. The letter W. or E. is affixed to the name of the sun, planet or star, to indicate that it is on the west, or east side of the moon. An observer on the earth's surface having...
Page 572 - 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.