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  2. Hour circle - Wikipedia

    en.wikipedia.org/wiki/Hour_circle

    Diagram illustrating the definition of the hour circle of a star In astronomy , the hour circle is the great circle through a given object and the two celestial poles . [ 1 ] Together with declination and distance (from the planet's centre of mass ), it determines the location of any celestial object .

  3. Nautical almanac - Wikipedia

    en.wikipedia.org/wiki/Nautical_almanac

    Meanwhile, the Reeds Nautical Almanac, published by Adlard Coles Nautical, has been in print since 1932, and in 1944 was used by landing craft involved in the Normandy landings. [ 5 ] The "Air Almanac" of the United States and Great Britain tabulates celestial coordinates for 10-minute intervals for use in aerial navigation .

  4. Harmonia Macrocosmica - Wikipedia

    en.wikipedia.org/wiki/Harmonia_Macrocosmica

    The Harmonia Macrocosmica is a star atlas written by Andreas Cellarius and published in 1660 by Johannes Janssonius.The first part of the atlas contains copper plate prints depicting the world systems of Claudius Ptolemy, Nicolaus Copernicus, and Tycho Brahe.

  5. Analemma - Wikipedia

    en.wikipedia.org/wiki/Analemma

    Afternoon analemma photo taken in 1998–99 in Murray Hill, New Jersey, U.S., by Jack Fishburn.The Bell Laboratories building is in the foreground. In astronomy, an analemma (/ ˌ æ n ə ˈ l ɛ m ə /; from Ancient Greek ἀνάλημμα (analēmma) 'support') [a] is a diagram showing the position of the Sun in the sky as seen from a fixed location on Earth at the same mean solar time over ...

  6. Astronomical clock - Wikipedia

    en.wikipedia.org/wiki/Astronomical_clock

    It has a concentric dial showing the 24-hour time, the date and zodiac, and the moon phase, and a star map dial with a dragon hand, and indicates the time of sunrise and sunset. [19] Třebíč. At the Třebíč Astronomical Observatory, a modern astronomical clock which shows the time in world cities, the time of sunrise and sunset, the date ...

  7. Sidereal time - Wikipedia

    en.wikipedia.org/wiki/Sidereal_time

    Sidereal time ("sidereal" pronounced / s aɪ ˈ d ɪər i əl, s ə-/ sy-DEER-ee-əl, sə-) is a system of timekeeping used especially by astronomers. Using sidereal time and the celestial coordinate system, it is easy to locate the positions of celestial objects in the night sky.

  8. Skalnate Pleso Atlas of the Heavens - Wikipedia

    en.wikipedia.org/wiki/Skalnate_Pleso_Atlas_of...

    The Atlas Coeli covers both hemispheres with 16 charts. The coordinate system is referred to equinox 1950.0 and the scale is 1° = 0.75 cm. There are six charts of the equatorial regions on a rectangular graticule, covering declinations from +25° to -25°; four charts for each hemisphere with straight, converging hour circles and concentric, equally-spaced declination circles covering ...

  9. Astronomical Almanac - Wikipedia

    en.wikipedia.org/wiki/Astronomical_Almanac

    The Astronomical Almanac [1] is an almanac published by the United Kingdom Hydrographic Office; it also includes data supplied by many scientists from around the world.On page vii, the listed major contributors to its various Sections are: H.M Nautical Almanac Office, United Kingdom Hydrographic Office; the Nautical Almanac Office, United States Naval Observatory; the Jet Propulsion Laboratory ...