Concept of wireless sensor network for future in-situ exploration of lunar ice using wireless impedance sensor

It is known that a wireless sensor network uses some sort of sensors to detect a physical quantity of interest, in general. The wireless sensor network is a potential tool for exploring the difficult-to-access area on the earth and the concept may be extended to space applications in future. Recently, lunar water has been detected by a few lunar missions using remote sensing techniques. The lunar water is expected to be in the form of ice at very low temperatures of permanently dark regions on the moon. To support the remote observations and also to find out potential ice bearing sites on the moon, in-situ measurement of the lunar ice is essential. However, a rover may not be able to reach the permanently shadowed regions due to terrain irregularity. One possibility to access such areas is to use a wireless sensor network on the lunar surface.In this paper, we have investigated a possibility of in-situ exploration of lunar ice by a wireless sensor network. The research issues related to the lunar wireless sensor network and a few possible solutions have been reviewed for the sake of completeness. A key component in the system is an ice sensor, which can measure the permittivity of the ice at appropriate frequency to differentiate with the soil. We suggest an impedance based sensor for this purpose, whose design aspects were reported earlier. We have successfully tested pure ice sample made from Milli-Q water in the laboratory environment and the results are shown in this paper.