The mapping of lunar radar scattering characteristics

Earth-based 12.6-cm wavelength radar mapping of the Moon: New views of impact melt distribution and mare physical properties

“…Radar images of the lunar surface are produced using the delayDoppler technique (e.g., Thompson and Dyce, 1966;Pettengill et al, 1974), which forms a coordinate system based on the round-trip time variations in the echoes and their frequency shift with respect to a chosen target location. The region of the Moon amenable to such mapping varies with libration, which brings different parts of the limb into view.…”

Focused 70-cm Wavelength Radar Mapping of the Moon

“…This results in a north-south ambiguity; every location in one hemisphere of a rotating spherical body has a symmetric location in the other hemisphere that has the same distance and velocity relative to the radar [19]. For a single observation, the echo powers from each pair of locations cannot be separated.…”

“…Because of the large distances and relatively low resolution, the imaging of planetary bodies using Earth-based radars normally only requires unfocused processing of the data, which is usually referred to in the field of planetary radar astronomy as delay-Doppler mapping [19]. The 9-arcmin beamwidth of the Arecibo antenna is about 30% of the angular diameter of the Moon, so a single observation reveals a large field of view on the lunar surface.…”

High-resolution lunar radar map at 70-cm wavelength

“…Simple rotations of Cartesian coordinate system rotations were used, as described by Pettengill et al (1974), and Thompson (1965Thompson ( , 1979. Once again, it was assumed that the Moon was a sphere with a diameter of 3476 km.…”