Cislunar plasma exploration with the SELENE radio science system Original Research Article

The SELENE Project of Japan includes three spacecraft: a main orbiting satellite and two subsatellites. Among many scientific objectives of the Project is the exploration of plasma formations above the lunar surface. The thin plasma layer above the area of the Moon, presented to the Sun, was first detected in radio occultation experiments conducted during 1972 with the Soviet lunar satellite “Luna-19”. The SELENE Project radio science experiment will be realized by means of a dual S- and X- band transmitter installed onboard the orbiter and Earth based antennas. The effect of the thin plasma layer near the Luna can be hidden by the fluctuations of the total electron content of the Earthʹs ionosphere. Dual spacecraft occultation configurations can remove partially the influence of the Earthʹs ionosphere. Several dual spacecraft configurations are discussed and upper error limits of total electron content measurements are estimated.