Imaging the Surface of Altair

@article{Monnier2007ImagingTS,
  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},
  journal={Science},
  year={2007},
  volume={317},
  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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264 Citations
Highly Influential Citations
28
Background Citations
98
Methods Citations
66
Results Citations
11

264 Citations

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References

SHOWING 1-10 OF 96 REFERENCES
Resolving the Effects of Rotation in Altair with Long-Baseline Interferometry
We report the successful fitting of a Roche model, with a surface temperature gradient following the von Zeipel gravity darkening law, to observations of Altair made with the Navy Prototype Optical…
Asymmetric Surface Brightness Distribution of Altair Observed with the Navy Prototype Optical Interferometer
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…
The polar wind of the fast rotating Be star Achernar. VINCI/VLTI interferometric observations of an
Be stars show evidence of mass loss and circumstellar envelopes (CSE), from UV resonance lines, near-IR excesses and the presence of episodic hydrogen emission lines. The geometry of these envelopes…
Altair’s Oblateness and Rotation Velocity from Long-Baseline Interferometry
We present infrared interferometric angular size measurements for the A7IV-V star Altair that indicate a noncircular projected disk brightness distribution. Given the known rapid rotation of this…
First Results from the CHARA Array. I. An Interferometric and Spectroscopic Study of the Fast Rotator α Leonis (Regulus)
We report on K-band interferometric observations of the bright, rapidly rotating star Regulus (type B7 V) made with the CHARA Array on Mount Wilson, California. Through a combination of…
Vega is a rapidly rotating star
TLDR
Optical interferometric observations show that Vega has the asymmetric brightness distribution of the bright, slightly offset polar axis of a star rotating at 93 per cent of its breakup speed, which leads to the prediction of an excess of near-infrared emission compared to the visible, in agreement with observations.
Optical interferometry in astronomy
Here I review the current state of the field of optical stellar interferometry, concentrating on ground-based work although a brief report of space interferometry missions is included. We pause both…
Mass and Angular Momentum Transfer in the Massive Algol Binary RY Persei
We present an investigation of the Hα emission-line variations observed in the massive Algol binary RY Per. We give new radial velocity data for the secondary based on our optical spectra and for the…
The spinning-top Be star Achernar from VLTI-VINCI
We report here the first observations of a rapidly rotating Be star, Eridani, using Earth-rotation synthesis on the Very Large Telescope (VLT) Interferometer. Our measures correspond to a 2a=2b= 1:56…
First Results from the CHARA Array. III. Oblateness, Rotational Velocity, and Gravity Darkening of Alderamin
We present observations of the A7 IV-V star Alderamin (α Cep, HR 8162, HD 203280) from the Georgia State University CHARA Array. These infrared interferometric angular size measurements indicate a…
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