Dr Wenzhe Fa
COFUND Senior Research Fellow at Trevelyan College (July-September 2016)
Wenzhe Fa is an Associate Professor in the School of Earth and Space Sciences, Peking University. He is a standout in the nascent field of Chinese planetary science and is one of the few scientists in the world who is working in the area of quantitative modeling of radar scattering from planetary surfaces, with particular emphasis on the effects of ice and surface roughness on the polarization characteristics of the reflected signal.
Water ice at the lunar poles provides important clues about both the delivery of water to the inner solar system during an early bombardment phase and lunar geology. It is also considered to be one of the most valuable resources in the solar system. However, previous orbital and Earth-based radar mapping has yielded conflicting interpretations for the existence of water. The U.S. Lunar Reconnaissance Orbiter spacecraft has recently returned global data for the moon. In this project, the latest radar data will be analysed, in combination with imagery and auxiliary topography, neutron spectroscopy and thermal infrared data, to reduce the ambiguity associated with the radar detection of water ice. Previous radar scattering models will be upgraded to include multiple scattering, and then quantitative analysis will be undertaken on the influence of lunar surface properties, such as roughness, dielectric constant, water ice and rock abundance, on the radar echo strength and polarization status. By studying how the radar maps vary from polar to non-polar craters, we will use the improved model to infer to what extent water ice is influencing these observations. Based on a better understanding of the radar measurements, we will be able to quantify the abundance of near-surface water ice in the lunar polar craters.