|Alcyone, Pleiades, is a typical blue giant|
NASA, ESA, AURA/Caltech, Palomar Observatoryderivative work:
Roberto Segnali all'Indiano - Pleiades_large.jpg. Licensed under Public Domain via Commons
Eta Lyrae is a blue subgiant with nearly similar metal abundance to Sun. The star belongs to spectral class B2.5IV and has apparent magnitude of +4.40. It is approximately 1390 light years from Earth.
The originally Arabic name Aladfar الأظفر al-’uz̧fur means "the talons (of the swooping eagle)" with Arab astronomers association of Lyra with an eagle.
|Blue giant Bellatrix compared to Algol B, the Sun, a red dwarf, and some planets|
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Licensed under GPLv2 via Commons
The name is applied to a wide variety of different types of stars with a moderate increase in size and luminosity compared to main-sequence stars of the same mass or temperature, and are hot enough to be called blue, meaning spectral class O, B, and sometimes early A.
Stars found in the blue giant region of the HR diagram can be in very different stages of their lives, but all are evolved stars that have largely exhausted their core hydrogen supplies.
Blue giants are much rarer than red giants, because they only develop from more massive and less common stars, and because they have short lives in the blue giant stage.
by User:Rursus. Licensed under CC BY-SA 3.0 via Commons