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Mars Micro-satellite Mission. Japanese micro-satellite mission to Mars to study the plasma environment and the solar wind interaction with a weakly-magnetized planet in response to Call for ideas of additional payload in Phobos-Soil mission for the investigation of Mars. Nozomi (Planet-B).
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Mars Micro-satellite Mission Japanese micro-satellite mission to Mars to study the plasma environment and the solar wind interaction with a weakly-magnetized planet in response to Call for ideas of additional payload in Phobos-Soil mission for the investigation of Mars
Nozomi (Planet-B) (Shinagawa, 2000) Motivation • Nozomi (Japanese Mars Orbiter) had to give up its injection into orbit around Mars due to unrecoverable malfunction. • No other spacecraft has performed the original scientific objectives of Nozomi. Therefore, numerous scientific questions are still unresolved. • Recent discoveries of water on Mars surface increase our interest in the atmospheric evolution and the loss process. • Existence of the crustal magnetic field provides a unique situation of the space plasma phenomena.
Payload Zone Mission Scenario • A micro-satellite for Mars orbiter will be developed in Japan so that it can fit for the additional payload zone on Phobos main bus. • After arriving at Mars, the micro-satellite will be separated from the mother ship at the Martian orbit, and it starts observing the upper atmosphere, ionosphere and the interaction region with the solar wind.
Scientific Objectives - 1 • The solar wind interaction with “mini” magnetosphere • The interaction with a weakly-magnetized planet • Reconnection, particle acceleration • Magnetospheric convection • Induced atmospheric escape • Atmospheric (plasma) escape • Potential influence on the atmospheric evolution • Comparative study with the escape from Earth • Diversity of the escape process and the flux variation • Where did the atmospheric particle go?
(Lundin, 1989) Scientific Objectives - 2 • Dynamics and structure of the ionosphere • Potential role of the crustal magnetic field • Altitude profile of Ne and Ni, and a role of the heat flux • Hole, cloud, streamer, tail ray – exist? • Ion pickup and magnetotail • Quantitative measurement of pickup ions • Asymmetric distribution of energetic ions and the ionospheric plasma • Acceleration of escaping ions in the magnetotail • Ionopause • Pressure balance • Momentum transfer and convection • Role of plasma wave in the mass loading • Turbulence, K-H instability
Spacecraft configuration and orbit Planned Orbit (To be revised) • Elliptical orbit (<4000 km x 80000 km from Mars center) Preferable to reduce the periapsis height below 300 km for the observation of Mars ionosphere • Inclination – TBD (depends on the orbit control ability) Preferable a mid-inclination orbit for the crustal magnetic field observation • Mission life : > 1 Mars year Baseline Configuration (To be revised) • Spinning platform • Control system for orbit and attitude maneuvers • Telemetry link with mother spacecraft by omni-directional antenna (Downlink via main bus) • Two booms for magnetometer and thermal plasma measurement • Two pairs of antenna for plasma wave measurement