VLBA Astrometric Observations of the Cassini Spacecraft at Saturn

  title={VLBA Astrometric Observations of the Cassini Spacecraft at Saturn},
  author={D. Llanwyn Jones and Edward Fomalont and Vivek Dhawan and Jonathan Romney and William M. Folkner and Gabor E. Lanyi and James S. Border and R. B. Dahlburg Jet Propulsion Laboratory and National Radio Astronomy Observatory},
  journal={arXiv: Earth and Planetary Astrophysics},
The planetary ephemeris is an essential tool for interplanetary spacecraft navigation, studies of solar system dynamics (including, for example, barycenter corrections for pulsar timing ephemeredes), the prediction of occultations, and tests of general relativity. We are carrying out a series of astrometric VLBI observations of the Cassini spacecraft currently in orbit around Saturn, using the Very Long Baseline Array (VLBA). These observations provide positions for the center of mass of Saturn… Expand
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