  Planetary radar observations offer the potential for probing the properties
of characteristics of solid bodies throughout the inner solar system and at
least as far as the orbit of Saturn. In addition to the direct scientific
value, precise orbital determinations can be obtained from planetary radar
observations, which are in turn valuable for mission planning or spacecraft
navigation and planetary defense. The next-generation Very Large Array would
not have to be equipped with a transmitter to be an important asset in the
world's planetary radar infrastructure. Bistatic radar, in which one antenna
transmits (e.g., Arecibo or Goldstone) and another receives, are used commonly
today, with the Green Bank Telescope (GBT) serving as a receiver. The improved
sensitivity of the ngVLA relative to the GBT would improve the signal-to-noise
ratios on many targets and increase the accessible volume specifically for
asteroids. Goldstone-ngVLA bistatic observations would have the potential of
rivaling the sensitivity of Arecibo, but with much wider sky access.

Earth and Planetary Astrophysics