Imaging the Surface of Altair

  title={Imaging the Surface of Altair},
  author={John D. Monnier and Ming Zhao and Ettore Pedretti and Nathalie D. Thureau and Michael J. Ireland and Philip S. Muirhead and J. P. Berger and Rafael Millan-Gabet and Gerard T. van Belle and Theo A. ten Brummelaar and Harold A. Mcalister and Stephen T. Ridgway and Nils Turner and Laszlo Sturmann and Judit Sturmann and David H. Berger},
  pages={342 - 345}
Spatially resolving the surfaces of nearby stars promises to advance our knowledge of stellar physics. Using optical long-baseline interferometry, we constructed a near-infrared image of the rapidly rotating hot star Altair with a resolution of <1 milliarcsecond. The image clearly reveals the strong effect of gravity darkening on the highly distorted stellar photosphere. Standard models for a uniformly rotating star cannot explain our findings, which appear to result from differential rotation… 
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