MDS Sub-Contracts to the Lunar & Planetary Institute (Houston, TX) to assist in developing space-bourn ground penetrating radar material analysis techniques under NASA contract

MDS and the Lunar and Planetary Institute have been awarded a grant by NASA to investigate the use of radar to detect hydrates on planetary bodies. Radar is a widely used tool for surveying chemical and mineral compositions; however, the response of hydrate to radar is unknown. Detection of hydrates on these bodies will aid in the understanding of planetary formation and evolution, astrobiology, and guide manned exploration of space.

Electromagnetic Characterization of Dusty-Ice and
Hydrate-Rich Materials in Planetary Environments

Principal Investigators: Essam Heggy, Stephen Clifford (Lunar & Planetary Institute), J. Osegovic, M.D. Max (MDS Research)

Radar has become an increasingly important tool in the investigation of a wide range of solar system objects, including the terrestrial planets, the Moon, asteroids and comets, and the icy satellites of the outer planets. Earth-based radar investigations of these objects have spanned several decades but, recently, these Earth-based studies have been supplemented by orbital spacecraft investigations using both synthetic aperture radar and sounding techniques. Of particular interest are the current radar investigations of Mars by MARSIS and SHARAD and of Titan by the Cassini Radar (Piccardi et al., 2005, Seu et al., 2004). Additional radar investigations of Mars, Europa, and Comet C67 (by the CONSERT radar (Koffman et al., 2002), aboard ESA's Rosetta comet mission, currently in flight) are also planned or under consideration. An important characteristic of each of these cold planetary environments is the presence of dusty-ice and hydrate-rich materials, whose properties and distribution can provide insights regarding the nature of these environments, the processes affecting them, and the origin and history of volatiles in planetary evolution.

The success of these current and future radar investigations (as well as our understanding of the data acquired by earlier Earth-based studies) is strongly dependent on how the composition, and temperature of the local environment affect the interaction of the radar wave with the planetary surface and its propagation in the subsurface. Unfortunately, the radar properties of the dusty ice- and hydrate-rich materials found in many cold planetary environments are not well-known and we have yet to characterize much of the potential parametric space associated with their occurrence.
To address this need, we propose to expand upon our previously-funded laboratory measurements of the electromagnetic properties of Mars analog materials, to include dusty-ice and hydrate-rich materials as they may occur in a wide range of cold planetary environments. Mixtures of dust (including volcanic, sedimentary, and meteoritic materials), water ice and hydrates, will be suggested as inferred from in-situ analysis and spectroscopic observations.
The proposed electromagnetic characterization measurements will be performed over the wide frequency range of 1 MHz to 3 GHz (hence covering all the current and proposed radar sounding frequencies), temperatures of ~110 K – 273 K, volumetric mixing ratios of dust-to-ice ranging from 0 – 100% and porosity range from 10 to 80%. These measurements will be made at the Lunar and Planetary Institute (Houston, Texas) in collaboration with Marine Desalination Systems L.L.C. (St. Petersburg, Florida), the Astromaterials group at the NASA Johnson Space Center (Houston, Texas) and various members of the MARSIS, SHARAD and CONSERT instrument teams.

The proposed research will provide a unique and important database of the geoelectrical properties of dusty-ice and hydrate-rich materials that, when combined with other remote-sensing data and geophysical models of the subsurface, will aid the analysis and interpretation of both current and future radar sounding data. This expanded understanding of radar properties is expected to increase the scientific yield from current radar investigations of dusty ice- and hydrate-rich environments and assist in defining the best frequencies and instrument parameters for future investigations. In addition, differences in the electromagnetic characteristics of dusty-ice and hydrate-rich materials may assist in resolving questions about the bulk composition of icy environments, where the thermal infrared spectral characteristics of candidate minerals may be subtle or indistinct.