22 relations: Angular distance, Apparent magnitude, Aquila (constellation), Binary star, Bright Star Catalogue, Catalogues of Fundamental Stars, Constellation, Durchmusterung, Flamsteed designation, Giant star, Henry Draper Catalogue, Hipparcos, Minute and second of arc, Monthly Notices of the Royal Astronomical Society, Orbital period, Parallax, Peculiar velocity, Rotating ellipsoidal variable, Smithsonian Astrophysical Observatory Star Catalog, Star system, Stellar classification, Variable star.
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.
New!!: 18 Aquilae and Angular distance ·
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.
New!!: 18 Aquilae and Apparent magnitude ·
Aquila is a constellation in the northern sky.
A binary star is a star system consisting of two stars orbiting around their common center of mass.
New!!: 18 Aquilae and Binary star ·
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.
New!!: 18 Aquilae and Bright Star Catalogue ·
The Catalogue of Fundamental Stars is a series of six astrometric catalogues of high precision positional data for a small selection of stars to define a celestial reference frame, which is a standard coordinate system for measuring positions of stars.
In modern astronomy, a constellation is a specific area of the celestial sphere as defined by the International Astronomical Union (IAU).
New!!: 18 Aquilae and Constellation ·
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.
New!!: 18 Aquilae and Durchmusterung ·
Flamsteed designations for stars are similar to Bayer designations, except that they use numbers instead of Greek and Roman letters.
New!!: 18 Aquilae and Flamsteed designation ·
A giant star is a star with substantially larger radius and luminosity than a main-sequence (or dwarf) star of the same surface temperature.
New!!: 18 Aquilae and Giant star ·
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.
New!!: 18 Aquilae and Hipparcos ·
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.
The orbital period is the time taken for a given object to make one complete orbit around another object.
New!!: 18 Aquilae and Orbital period ·
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.
New!!: 18 Aquilae and Parallax ·
Peculiar motion or peculiar velocity refers to the true velocity of an object, relative to a rest frame.
New!!: 18 Aquilae and Peculiar velocity ·
Rotating ellipsoidal variables are a class of variable star.
The Smithsonian Astrophysical Observatory Star Catalog is an astrometric star catalogue.
A star system or stellar system is a small number of stars that orbit each other, bound by gravitational attraction.
New!!: 18 Aquilae and Star system ·
In astronomy, stellar classification is the classification of stars based on their spectral characteristics.
A variable star is a star whose brightness as seen from Earth (its apparent magnitude) fluctuates.
New!!: 18 Aquilae and Variable star ·