Web Publications

High Angular Resolution Observations of Mira

pdf

Margarita Karovska

Harvard-Smithsopnian Center for Astrophysics

60 Garden Street

Cambridge, MA 02138

Presented at the AAVSO Session on Mira Stars (part of the 85th Annual Meeting), November 1, 1996

Abstract

The results of high angular resolution observations of Mira, the prototype star of the class of Mira-type variables, are reviewed, including the detection of substanial asymmetries in its atmosphere. Because of these asymmetries and the effect of the extended atmosphere, it is difficult to determine a photospheric diameter, a crucial parameter for establishing the effective temperature scale and the mode of pulsation. This parameter could be derived using accurate measurements of the diameter and the brightness distribution across the stellar disk as a function of wavelength and pulsation phase, in conjunction with detailed model atmosphere calculations.