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VY Canis Majoris: The Astrophysical Basis of Its Luminosity

Roberta M. Humphreys
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Abstract

The luminosity of the famous red supergiant VY CMa (L ~ 4 - 5 x 10e5 Lsun) 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.

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Roberta M. Humphreys. 2006-10-13. VY Canis Majoris: The Astrophysical Basis of Its Luminosity. https://arxiv.org/abs/astro-ph/0610433

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