Mercury has a unique and complex space environment with its weak global magnetic field, intense solar wind, tenuous exosphere, and magnetospheric plasma particles. This complex system makes Mercury an excellent science target to understand effects of the solar wind to planetary environments. In addition, investigating Mercury’s dynamic magnetosphere also plays a key role to understand extreme exoplanetary environment and its habitability conditions against strong stellar winds. BepiColombo, a joint mission to Mercury by the European Space Agency and Japan Aerospace Exploration Agency, will address remaining open questions using two spacecraft, Mio and the Mercury Planetary Orbiter. Mio is a spin-stabilized spacecraft designed to investigate Mercury’s space environment, with a powerful suite of plasma instruments, a spectral imager for the exosphere, and a dust monitor. Because of strong constraints on operations during its orbiting phase around Mercury, sophisticated observation and downlink plans are required in order to maximize science outputs. This paper gives an overview of the Mio spacecraft and its mission, operations plan, and data handling and archiving.

中文翻译：

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Mio——首次全面探索水星空间环境：任务概述

水星具有独特而复杂的空间环境，其全球磁场较弱，太阳风强烈，外逸层稀薄，磁层等离子体粒子。这个复杂的系统使水星成为了解太阳风对行星环境影响的绝佳科学目标。此外，研究水星的动态磁层对于了解极端的系外行星环境及其抵抗强恒星风的宜居条件也起着关键作用。BepiColombo 是欧洲航天局和日本宇宙航空研究开发机构对水星的联合任务，将使用两个航天器 Mio 和水星行星轨道器解决剩余的悬而未决的问题。Mio 是一种自旋稳定的航天器，旨在研究水星的空间环境，配备一套强大的等离子仪器，一个用于外逸层的光谱成像仪和一个灰尘监测器。由于在围绕水星运行的轨道阶段运行受到强烈限制，因此需要复杂的观测和下行链路计划，以最大限度地提高科学产出。本文概述了 Mio 航天器及其任务、运营计划以及数据处理和存档。