The Orbit of the Close Companion of Polaris: Hubble Space Telescope Imaging, 2007 to 2014

@article{Evans2018TheOO,
  title={The Orbit of the Close Companion of Polaris: Hubble Space Telescope Imaging, 2007 to 2014},
  author={Nancy Remage Evans and Margarita Karovska and Howard E. Bond and Gail H. Schaefer and Kailash C. Sahu and Jennifer Mack and Edmund P. Nelan and Alexandre Gallenne and Evan Tingle},
  journal={The Astrophysical Journal},
  year={2018},
  volume={863}
}
As part of a program to determine the dynamical masses of Cepheids, we have imaged the nearest and brightest Cepheid, Polaris, with the Hubble Space Telescope (HST) Wide Field Planetary Camera 2 and Wide Field Camera 3. Observations were obtained at three epochs between 2007 and 2014. In these images, as in HST frames obtained in 2005 and 2006, which we discussed in a 2008 paper, we resolve the close companion Polaris Ab from the Cepheid Polaris Aa. Because of the small separation and large… 

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