An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

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Number of Results: 2 Search : A star
A star
  ستاره‌ی A   
setâre-ye A

Fr.: étoile de type A   

A star whose spectrum shows strong hydrogen → Balmer lines accompanied by many faint to moderately strong metallic lines. In contrast to B and O stars, the lines of He I and He II are absent. Their surface temperature ranges from 7,500 to 10,000 K. The main metallic lines seen in A-type stars are those of Fe I and Fe II, Cr I and II, Ti I and II, and account for about two-thirds of all lines. Some famous examples of A star are: → Sirius; → Deneb, → Altair, and → Vega. Also known as A-type star.

A, letter of alphabet used in the → Harvard classification; → type; → star.

post-planetary nebula star
  ستاره‌ی ِ پسا-میغ ِ سیاره‌ای   
setâre-ye pasâ-miq-e sayyâre-yi

Fr.: étoile post-nébuleuse planétaire   

An evolved star whose → planetary nebula has dissipated.

post-; → planetary; → nebula; → star.