VY Canis Majoris: The Astrophysical Basis of Its Luminosity
نویسنده
چکیده
The luminosity of the famous red supergiant VY CMa ( L ∼ 4− 5× 105L⊙) is well-determined from its spectral energy distribution and distance, and places it near the empirical upper luminosity limit for cool hypergiants. In contrast, its surface temperature is fundamentally ill-defined. Both contradict a recent paper by Massey, Levesque and Plez (2006). Implications for its location on the HR Diagram and its apparent size are discussed. Subject headings: stars: late–type — stars: individual(VY CMa) — supergiants
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