Asymmetric Surface Brightness Distribution of Altair Observed with the Navy Prototype Optical Interferometer

  title={Asymmetric Surface Brightness Distribution of Altair Observed with the Navy Prototype Optical Interferometer},
  author={Naoko Ohishi and Tyler E. Nordgren and Donald J. Hutter},
  journal={The Astrophysical Journal},
  pages={463 - 471}
An asymmetric surface brightness distribution of the rapidly rotating A7 IV-V star Altair has been measured by the Navy Prototype Optical Interferometer (NPOI). The observations were recorded simultaneously using a triangle with long baselines of 30, 37, and 64 m, on 19 spectral channels, covering the wavelength range of 520-850 nm. The outstanding characteristics of these observations are (1) high resolution with the minimum fringe spacing of 1.7 mas, easily resolving the 3 mas stellar disk… 
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