A Precision Test of Hipparcos Systematics toward the Hyades

  title={A Precision Test of Hipparcos Systematics toward the Hyades},
  author={Vijay K. Narayanan and Andrew P. Gould},
  journal={The Astrophysical Journal},
We propose a test that can in principle detect any systematic errors in the Hipparcos parallaxes toward the Hyades cluster at the level of 0.3 mas. We show that the statistical parallax algorithm subsumes the classical moving cluster methods and provides more precise estimates of the distance and the first two moments of the velocity distribution of the Hyades cluster, namely, its bulk space velocity and the velocity dispersion tensor. To test the Hipparcos parallaxes, we first rescale the bulk… 

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