Exploring the Plasma Environment of Mars

Despite more than 40 years of in situ measurement, we still do not have a complete survey of particles, fields in the near Mars space. The Sino-Russian Joint Mars-Phobos Exploration program provides unique opportunity to investigate the global structure of the solar wind and Mars interaction region. Mars orbiter, YH-1 will explore the Martian space environment, to determine characteristics in different regions and their evolution with solar wind conditions, and to investigate the water escape process related with solar wind forcing. For these purposes, YH-1 will carry a plasma package consisting of two identical ion analyzers, and one electron analyzer, which aim at monitoring the plasma with energy from 0.02 keV up to 10 keV, providing mass analysis of ions in the mass range from 1 to 44\,au with fast time and fine energy resolution. Together with the magnetic field experiment on board YH-1, the plasma package will be the first to give full insight into the local plasma characteristics near the planet, to determine the possible total ion escape rate (particles/s) for the major ion species. The scientific objectives of the plasma experiment, as well as design of the instrument are presented in the paper.