21 relations: A-type main-sequence star, Angular distance, Apparent magnitude, Aquarius (constellation), Bayer designation, Bortle scale, Bright Star Catalogue, Carnegie Institution for Science, 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, Star, 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 (e.g. astronomy and geophysics), the angular distance (angular separation, apparent distance, or apparent separation) between two point objects, as viewed from a location different from either of these objects, is the angle of length between the two directions originating from the observer and pointing toward these two objects.
The apparent magnitude of a celestial object is a number that is a measure of its brightness as seen by an observer on Earth.
Aquarius is a constellation of the zodiac, situated between Capricornus and Pisces.
A Bayer designation is a stellar designation in which a specific star is identified by a Greek letter, followed by the genitive form of its parent constellation's Latin name.
The Bortle scale is a nine-level numeric scale that measures the night sky's brightness of a particular location.
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 Carnegie Institution of Washington (the organization's legal name), known also for public purposes as the Carnegie Institution for Science (CIS), is an organization in the United States established to fund and perform scientific research.
The celestial equator is the great circle of the imaginary celestial sphere on the same plane as the equator of Earth.
A constellation is a group of stars that are considered to form imaginary outlines or meaningful patterns on the celestial sphere, typically representing animals, mythological people or gods, mythological creatures, or manufactured devices.
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.
A Flamsteed designation is a combination of a number and constellation name that uniquely identifies most naked eye stars in the modern constellations visible from southern England.
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.
A minute of arc, arcminute (arcmin), arc minute, or minute arc is a unit of angular measurement equal to 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.
The Smithsonian Astrophysical Observatory Star Catalog is an astrometric star catalogue.
A star is type of astronomical object consisting of a luminous spheroid of plasma held together by its own gravity.
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.