English

UrHip Proper Motion Catalog

Solar and Stellar Astrophysics 2015-10-14 v1

Abstract

Proper motions are computed and collected in a catalog using the Hipparcos positions (epoch 1991.25) and URAT1 positions (epoch 2012.3 to 2014.6). The goal is to obtain a significant improvement on the proper motion accuracy of single stars in the northern hemisphere, and to identify new astrometric binaries perturbed by orbital motion. For binaries and multiple systems, the longer baseline of Tycho2 (~ 100 yr) makes it more reliable despite its larger formal uncertainties. The resulting proper motions obtained for 67,340 stars have a consequent gain in accuracy by a factor of ~ 3 compared to Hipparcos. Comparison between UrHip and Hipparcos shows that they are reasonably close, but also reveals stars with large discrepant proper motions, a fraction of which are potential binary candidates.

Keywords

Cite

@article{arxiv.1509.05626,
  title  = {UrHip Proper Motion Catalog},
  author = {Julien Frouard and Bryan N. Dorland and Valeri V. Makarov and Norbert Zacharias and Charlie T. Finch},
  journal= {arXiv preprint arXiv:1509.05626},
  year   = {2015}
}

Comments

11 pages, 5 figures, accepted for publication in AJ

R2 v1 2026-06-22T10:59:49.785Z