The luminosity of the B2 hypergiant HD 80077.

Abstract

The extremely bright and relatively stable hypergiant HD 80077 is an enigmatic object. Since the star is assumed to have a luminosity of 2 x 10 exp 6, considerable variability and a large mass loss rate would be expected. However, its mass loss rate of (5 +10/-3) x 10 exp -6 solar mass/yr and its variability are very low with respect to its luminosity. The star is assumed to be a member of the cluster Pismis 11, and therefore to have a known distance. The above-mentioned luminosity has been derived using the apparent visual magnitude, the bolometric correction and the distance to Pismis 11. Indications that the star is not a member of Pismis 11, but a foreground star, therefore having a lower luminosity have been looked for. For this, no evidence has been found.