subradar
adjEtymology From sub- + radar.
1
Below an area being investigated by radar.
- One of the major difficulties with this method is that the largely unknown planetary topography can introduce errors in round trip travel times as much as 5 μs (i.e., the subradar point could be a mountaintop or a valley) […]1993, Clifford M. Will, Theory and Experiment in Gravitational Physics, page 175: