Polar Water Ice Deposits:

The Contrast Between Mercury and the Moon

极区水冰沉积：水星与月球的对比

主讲人：David T. Blewett 研究员

        JohnsHopkins University Applied Physics Lab, USA

时  间：2017年8月29日，上午10:00 – 11:30

地  点：遥感楼517会议室

摘要：The Moon and Mercury both haverelatively small obliquity (tilts of the rotation axis). As a result,low-elevation areas near the poles may be in permanent shadow, and hence haveexperienced very low temperatures over long periods of time. The conditions inthese cold traps are suitable for accumulation of volatile compounds, includingwater ice. A variety of remote-sensing datasets indicate that ice is indeedpresent at the lunar and mercurian poles. I will review evidence for ice thatcomes from Earth-based radar, mapping of polar shadows, neutron spectrometry,temperature modeling and mapping, and albedo mapping. There are importantdifferences between the characteristics of the polar deposits on Mercury andthose on the Moon that suggest differing histories of delivery of volatiles tothe two worlds.

报告人简介：DavidT. Blewett is a member of the Principal Professional Staff in the PlanetaryExploration Group at the Johns Hopkins University Applied Physics Laboratory inMaryland, USA. He was a member of the science team for the NASA MESSENGER Mercury orbiter mission. Hewas also a member of the Dawn scienceteam for the Vesta phase of the mission. His research interests are planetarysurface processes, space weathering, remote sensing, and reflectancespectroscopy. He received a bachelor's degree in astronomy and astrophysics fromthe University of Pennsylvania, and master's and Ph.D. degrees (geology andgeophysics) from the University of Hawaii.