The Age of the Oldest Stars in the Local Galactic Disk from Hipparcos Parallaxes of G and K Subgiants

  title={The Age of the Oldest Stars in the Local Galactic Disk from Hipparcos Parallaxes of G and K Subgiants},
  author={A. Sandage and L. Lubin and D. VandenBerg},
  journal={Publications of the Astronomical Society of the Pacific},
ABSTRACT We review the history of the discovery of field subgiant stars, the role that they played in the development of the early understanding of stellar evolution, and their importance in the age dating of the Galactic disk. We use the cataloged data from the Hipparcos satellite in this latter capacity. Based on Hipparcos parallaxes with relative accuracies of \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs… Expand
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