Geologic Studies of Planetary Surfaces Using Radar Polarimetric Imaging

Abstract

| Radar is a useful remote sensing tool for studying planetary geology because it is sensitive to the composition, structure, and roughness of the surface and can penetrate some materials to reveal buried terrain. The Arecibo Observatory radar system transmits a single sense of circular polarization, and both senses of circular polarization are received, which allows for the construction of the Stokes polarization vector. From the Stokes vector, daughter products such as the circular polarization ratio, the degree of linear polarization, and linear polarization angle are obtained. Recent polarimetric imaging using Arecibo has included Venus and the Moon. These observations can be compared to radar data for terrestrial surfaces to better understand surface physical properties and regional geologic evolution. For example, polarimetric radar studies of volcanic settings on Venus, the Moon, and Earth display some similarities, but also illustrate a variety of different emplacement and erosion mechanisms. Polarimetric radar data provide important information about surface properties beyond what can be obtained from single-polarization radar.Future observations using polarimetric synthetic aperture radar will provide information on roughness, composition, and stratigraphy that will support a broader interpretation of surface evolution.

Global distribution of lunar impact melt flows

“…Targets with little subsurface scattering have low DLP, targets with diffuse subsurface scattering have moderate DLP, and targets with buried interfaces have high DLP (see Fig. 1 in Carter et al, 2011). To distinguish between these scenarios, we calculated the DLP for Glushko crater (Fig.…”

Identification of tectonic deformations on the south polar surface of the moon

“…4e) Carter et al, 2011). The high CPR obtained from the region of the debris avalanche cannot be due to ice particles since the region is illuminated by the sun and therefore ice particles would not sustain in the region when the sun heats up the surface.…”

Comparing Compact and Quadrature Polarimetric SAR Performance

“…(i) For decades, classical radar astronomy [15] has had success using the values of individual child parameters of the four-element Stokes vector, such as degree of polarization (m), circular-polarization ratio (CPR), and degree of linear polarization m L . These as well as others could be useful in classification applications of Earthoriented CP radar data.…”

“…As is well known in radar astronomy [15], usually, the dominant component in response to right-circular (R) transmitted polarization is RL. Yes, RL.…”