An Etymological Dictionary of Astronomy and Astrophysics
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فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

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Number of Results: 3 Search : variable star
extrinsic variable star
  ستاره‌ی ِ ورتنده‌ی ِ برونگین   
setâre-ye vartande-ye borungin

Fr.: étoile variable extrinsèque   

A star whose variation in apparent brightness is not due to changes in the star itself but to some external cause, such as eclipsing by a companion.

extrinsic; → variable; → star.

variable star
  ستاره‌ی ِ ورتنده   
setâre-ye vartandé

Fr.: étoile variable   

A star whose luminosity changes over periods of time; there are many reasons and many types. → cataclysmic variable; → Cepheid; → pulsating star; → nova; → long-period variable; → short-period variable; → Luminous Blue Variable (LBV); etc.

variable; → star.

variable star designation
  نامگزینی ِ ستاره‌ی ِ ورتنده   
nâmgozini-ye setâre-ye vartandé

Fr.: designation des étoiles variables   

A set of conventions used for naming variable stars. Stars with existing → Bayer designations are not given new designations. Alternatively, the letters R through Z are used followed by the Latin genitive of the name of the hosting constellation. Otherwise, two letters of alphabet are used (334 combinations) with the Latin genitive of the name of the constellation. Finally, the letter V (variable) is used followed by numbers 335, 336, and so on. Some examples are: → P Cygni, → T Tauri, → FU Orionis, → EX Lupi, and V509 Cassiopeiae.

variable; → star; → designation.