19 relations: A-type main-sequence star, Angular distance, Apparent magnitude, Aquarius (constellation), Binary star, Bortle scale, Bright Star Catalogue, Celestial equator, Constellation, Durchmusterung, Flamsteed designation, Henry Draper Catalogue, Hipparcos, Minute and second of arc, Monthly Notices of the Royal Astronomical Society, Parallax, Smithsonian Astrophysical Observatory Star Catalog, Stellar classification, Stellar rotation.
An A-type main-sequence star (A V) or A dwarf star is a main-sequence (hydrogen-burning) star of spectral type A and luminosity class V. These stars have spectra which are defined by strong hydrogen Balmer absorption lines.
In mathematics (in particular geometry and trigonometry) and all natural sciences (including astronomy, geophysics, etc.), the angular distance (angular separation, apparent distance, or apparent separation) between two point objects, as observed from a location different from either of these objects, is the size of the angle between the two directions originating from the observer and pointing towards these two objects.
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The apparent magnitude (m) of a celestial object is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere.
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Aquarius is a constellation of the zodiac, situated between Capricornus and Pisces.
A binary star is a star system consisting of two stars orbiting around their common center of mass.
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The Bortle scale is a nine-level numeric scale that measures the night sky's brightness of a particular location.
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The Bright Star Catalogue, also known as the Yale Catalogue of Bright Stars or Yale Bright Star Catalogue, is a star catalogue that lists all stars of stellar magnitude 6.5 or brighter, which is roughly every star visible to the naked eye from Earth.
The celestial equator is a great circle on the imaginary celestial sphere, in the same plane as the Earth's equator.
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In modern astronomy, a constellation is a specific area of the celestial sphere as defined by the International Astronomical Union (IAU).
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In astronomy, Durchmusterung or Bonner Durchmusterung (BD), is the comprehensive astrometric star catalogue of the whole sky, compiled by the Bonn Observatory (Germany) from 1859 to 1903.
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Flamsteed designations for stars are similar to Bayer designations, except that they use numbers instead of Greek and Roman letters.
The Henry Draper Catalogue (HD) is an astronomical star catalogue published between 1918 and 1924, giving spectroscopic classifications for 225,300 stars; it was later expanded by the Henry Draper Extension (HDE), published between 1925 and 1936, which gave classifications for 46,850 more stars, and by the Henry Draper Extension Charts (HDEC), published from 1937 to 1949 in the form of charts, which gave classifications for 86,933 more stars.
Hipparcos was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993.
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A minute of arc (MOA), arcminute (arcmin) or minute arc is a unit of angular measurement equal to one-sixtieth of one degree.
Monthly Notices of the Royal Astronomical Society (MNRAS) is a peer-reviewed scientific journal covering research in astronomy and astrophysics.
Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those two lines.
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The Smithsonian Astrophysical Observatory Star Catalog is an astrometric star catalogue.
In astronomy, stellar classification is the classification of stars based on their spectral characteristics.
Stellar rotation is the angular motion of a star about its axis.
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