17 relations: A-type main-sequence star, Apparent magnitude, Astronomical unit, Barycenter, Bayer designation, Be star, Binary star, Constellation, Corona Borealis, Epoch (astronomy), International Celestial Reference System, Latinisation of names, Light-year, Main sequence, Red giant, Shell star, Stellar classification.
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.
The apparent magnitude of a celestial object is a number that is a measure of its brightness as seen by an observer on Earth.
The astronomical unit (symbol: au, ua, or AU) is a unit of length, roughly the distance from Earth to the Sun.
The barycenter (or barycentre; from the Ancient Greek βαρύς heavy + κέντρον centre) is the center of mass of two or more bodies that are orbiting each other, which is the point around which they both orbit.
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.
Be Stars are a heterogeneous set of stars with B spectral types and emission lines.
A binary star is a star system consisting of two stars orbiting around their common barycenter.
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.
Corona Borealis is a small constellation in the Northern Celestial Hemisphere.
In astronomy, an epoch is a moment in time used as a reference point for some time-varying astronomical quantity, such as the celestial coordinates or elliptical orbital elements of a celestial body, because these are subject to perturbations and vary with time.
The International Celestial Reference System (ICRS) is the current standard celestial reference system adopted by the International Astronomical Union (IAU).
Latinisation or Latinization is the practice of rendering a non-Latin name (or word) in a Latin style.
The light-year is a unit of length used to express astronomical distances and measures about 9.5 trillion kilometres or 5.9 trillion miles.
In astronomy, the main sequence is a continuous and distinctive band of stars that appear on plots of stellar color versus brightness.
A red giant is a luminous giant star of low or intermediate mass (roughly 0.3–8 solar masses) in a late phase of stellar evolution.
A shell star is a star having a spectrum that exhibits features indicating a circumstellar disc of gas surrounding the star at the equator.
In astronomy, stellar classification is the classification of stars based on their spectral characteristics.