ExoCat-1: The Nearby Stellar Systems Catalog for Exoplanet Imaging Missions

We present the first version of a Nearby Stellar Systems Catalog for Exoplanet Imaging Missions (dubbed by the direct imaging community as "ExoCat") for use in exoplanet direct imaging mission planning. This version, ExoCat-1, includes 2347 stars taken from the Hipparcos Catalogue with measured parallaxes > 33.33 mas (corresponding to a distance of 30 pc). This sample is nearly complete down to V=8, corresponding to stars brighter than ~0.5 solar luminosities (late G-/early K-type dwarf stars at the 30 pc distance limit). For each star we provide astrometry (including Equatorial and Galactic coordinates, parallax, and proper motions), Johnson B and V magnitudes (converted from Hipparcos or Tycho data or taken from the literature), and Ks-band magnitudes from 2MASS (for fainter stars) or K-band magnitudes taken from the literature and converted to 2MASS Ks magnitudes (for bright stars). Using these data we estimate stellar luminosity, effective temperature, stellar radius (in solar and angular units), Earth-equivalent insolation distances (in AU and in angular units), and fraction planet brightness for an exo=Earth at the Earth-equivalent insolation distance. We provide published spectral types and simple labels on stellar type for quick assessment of design reference mission-selected targets lists. The number of known exoplanet companions is indicated for each star, and for bright stars (V<7) we provide separations and delta-magnitudes for the brightest stellar companion within 10 arcseconds. Other important stellar data such as log(g), chromospheric activity level, and age estimates are provided where readily available. ExoCat-1 can be found through the Exoplanets Exploration Program (ExEP) website.