Pre-flight Calibration and Near-Earth Commissioning Results of the Mercury Plasma Particle Experiment (MPPE) Onboard MMO (Mio)

Abstract

BepiColombo Mio (previously called MMO: Mercury Magnetospheric Orbiter) was successfully launched by Ariane 5 from Kourou, French Guiana on October 20, 2018. The Mercury Plasma/Particle Experiment (MPPE) is a comprehensive instrument package onboard Mio spacecraft used for plasma, high-energy particle and energetic neutral atom measurements. It consists of seven sensors including two Mercury Electron Analyzers (MEA1 and MEA2), Mercury Ion Analyzer (MIA), Mass Spectrum Analyzer (MSA), High Energy Particle instrument for electron (HEP-ele), High Energy Particle instrument for ion (HEPion), and Energetic Neutrals Analyzer (ENA). Significant efforts were made pre-flight to calibrate all of the MPPE sensors at the appropriate facilities on the ground. High voltage commissioning of MPPE analyzers was successfully performed between June and August 2019 and in February 2020 following the completion of the low voltage commissioning in November 2018. Although all of the MPPE analyzers are now ready to begin observation, the full service performance has been delayed until Mio's arrival at Mercury. Most of the fields of view (FOVs) of the MPPE analyzers are blocked by the thermal shield surrounding the Mio spacecraft during the cruising phase. Together with other instruments on Mio including Magnetic Field Investigation (MGF) and Plasma Wave Investigation (PWI) that measure plasma field parameters, MPPE will contribute to the comprehensive understand-The BepiColombo mission to Mercury Edited by

MESSENGER Observations of Planetary Ion Enhancements at Mercury's Northern Magnetospheric Cusp During Flux Transfer Event Showers

“…A joint European Space Agency (ESA)‐Japan Aerospace Exploration Agency (JAXA) mission, BepiColombo (Milillo et al., 2020 ), consisting of the Mercury Planetary Orbiter (MPO) and the Mercury Magnetospheric Orbiter (MMO, or Mio), made its first flyby of Mercury in October 2021 with Mercury orbit insertion scheduled in late 2025 or early 2026. BepiColombo will provide many comprehensive measurements on Mercury's magnetosphere and exosphere, especially those higher resolutions measurements for different ion species, that is, Mercury Plasma Particle Experiment (MPPE) (Saito et al., 2021 ) onboard Mio, and neutrals, that is, Search for Exospheric Refilling and Emitted Natural Abundances (SERENA) (Orsini et al., 2021 ). Moreover, MPO and Mio will have much broader altitudinal coverage of both northern and southern cusps than MESSENGER was able to achieve.…”

Does Phobos Reflect Solar Wind Protons? Mars Express Special Flyby Operations With and Without the Presence of Phobos

“…As the reflected particles can characterize the impinging proton flux at the surface from the orbiter (Futaana et al, 2006(Futaana et al, , 2013Wieser et al, 2010), the reflected particle measurements open a new pathway for remotely measuring the solar wind proton characteristics impinging on a surface in space. This technique can be applied to other airless bodies such as Mercury (with the BepiColombo mission; Saito et al, 2010Saito et al, , 2021 and the Jovian moons.…”

Particles and Photons as Drivers for Particle Release from the Surfaces of the Moon and Mercury

“…In late 2025, the BepiColombo mission will enter Mercury orbit. It also carries instruments for the detection of energetic neutral atoms (Saito et al 2021;Orsini et al 2021) so that similar studies will be executed at Mercury. Fortunately, what was learned from the lunar studies on particle reflection applies to other planetary bodies without an atmosphere, for example for Mercury .…”