The American Ephemeris and Nautical AlmanacU.S. Government Printing Office, 1852 - Nautical almanacs |
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53 Arietis Aldebaran W Apparent Declination APPARENT PLACES Apparent Right Ascension Aquarii Aquila ASCENSION AND DECLINATION Astr Cancri Capricor Ceti corr Eclipse Disapp Eclipse Reapp Egress 20 Ephemeris Factor for Second Fomalhaut E GREENWICH MEAN Horizontal Parallax Ingress 22 Jupiter W Leonis Libræ longitude LUNAR DISTANCES Mars Mean Solar Meridian hour Meridian Transit Midnight Moon MOON'S RIGHT ASCENSION Nachr Name and Position Noon and Meridian North Occult Ophiuchi P. L. of Diff P. L. of VIh parallax Pegasi Piscium Pollux Regulus PRINCIPAL FIXED STARS R.A. Dec R.A. In Dec refraction Regulus Spica Sagittarii Saturn Pollux Saturn W Scorpii Second Diff's Semidi Shadow Ingress Sidereal Day Sidereal Minute Spica Antares Spica E Star's Name sun's Table Tauri Thur TRANSIT AT WASHINGTON Transit Egress Tues UPPER TRANSIT Venus Virginis Washington Mean WASHINGTON MERIDIAN Washington Sidereal Noon XXIh
Popular passages
Page 482 - Table IV, for finding the latitude from an observed altitude of Polaris, is constructed for— ( 1 ) An altitude of Polaris equal to 45°. ( 2 ) A declination of Polaris equal to -f- 88° 43'.
Page 457 - The Astronomical Day commences at noon on the civil day of the same date. It also comprises twenty-four hours; but they are reckoned from 0 to 24, and from the noon of one day to that of the next following. The...
Page 457 - January 9th, 2 h , astronomical time. The rule, then, for the transformation of civil time into astronomical time is this: — If the civil time is marked AM, take one from the day and add twelve to the hours, and the result is the astronomical time wanted...
Page 456 - EPHEMERIS FOR THE MERIDIAN OF GREENWICH. THE greater portion of this Ephemeris, embracing the positions of the sun and moon; the distances of the moon from the centres of the sun and the four most conspicuous planets, and from certain fixed stars; the ephemerides of the planets Mercury, Venus, Mars, Jupiter, and Saturn, is designed for the special use of navigators. The remainder contains...
Page 479 - Mr. HUGH BREEN'S results contained in his paper On the Corrections of LINDENAU'S Elements of Mars, published in the Memoirs of the Royal Astronomical Society, Vol. XX., have also been discussed and applied ; and LE VERRIER'S sreular variations of the elements are likewise adopted.
Page 460 - XVin. of each Month. Lunar Distances. — These pages contain, for every third hour of Greenwich mean time, the angular distances, available for the determination of the longitude, of the apparent centre of the Moon from the Sun, the larger plane.ts and certain stars as they would appear from the centre of the Earth. When a Lunar Distance has been observed on the surface of the Earth, and...
Page 457 - Mean Sun, is supposed to move in the equator with a uniform 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 456 - ... 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 463 - 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 t, which may be obtained in seconds by the formulae log. м'= 1.88187 log. Я'= 1.3757 a' = A