Vega is a rapidly rotating star

  title={Vega is a rapidly rotating star},
  author={Deane M. Peterson and Christian A. Hummel and Thomas A. Pauls and J. T. Armstrong and J. A. Benson and G. Charmaine Gilbreath and Robert B. Hindsley and Donald J. Hutter and Kenneth J. Johnston and David Mozurkewich and Henrique R. Schmitt},
Vega, the second brightest star in the northern hemisphere, serves as a primary spectral type standard. Although its spectrum is dominated by broad hydrogen lines, the narrower lines of the heavy elements suggested slow to moderate rotation, giving confidence that the ground-based calibration of its visible spectrum could be safely extrapolated into the ultraviolet and near-infrared (through atmosphere models), where it also serves as the primary photometric calibrator. But there have been… 
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Hubble Space Telescope Absolute Spectrophotometry of Vega from the Far-Ultraviolet to the Infrared
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