Direct Detection of the Close Companion of Polaris with the Hubble Space Telescope

@article{Evans2005DirectDO,
  title={Direct Detection of the Close Companion of Polaris with the Hubble Space Telescope},
  author={Nancy Remage Evans and Gail H. Schaefer and Howard E. Bond and Giuseppe Bono and Margarita Karovska and Edmund P. Nelan and Dimitar D. Sasselov and Brian D. Mason},
  journal={The Astronomical Journal},
  year={2005},
  volume={136},
  pages={1137-1146}
}
Polaris, the nearest and brightest classical Cepheid, is a single-lined spectroscopic binary with an orbital period of 30 yr. Using the High Resolution Channel of the Advanced Camera for Surveys on board the Hubble Space Telescope (HST) at a wavelength of ~2255 A, we have directly detected the faint companion at a separation of 017. A second HST observation 1.04 yr later confirms orbital motion in a retrograde direction. By combining our two measures with the spectroscopic orbit of Kamper and… 
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