The ESA/JAXA BepiColombo mission is currently on its way to Mercury, aiming to unveil the secrets held by the innermost planet of the Solar System. The radio tracking measurements, in combination with the data acquired by the onboard accelerometer, will enable a precise navigation of the spacecraft addressing the scientific objectives of the mission. A series of planetary flybys are required during the interplanetary transfer orbit to save propellant for the orbital insertion around Mercury. We present here a joint analysis of the radio tracking and accelerometer measurements collected during the second Venus flyby and the first two Mercury flybys. A precise orbit determination process is carried out to yield a combined adjustment of the spacecraft trajectory and parameters associated with dynamical and observational modeling. The accelerometer data enabled the detection of unmodeled dynamical perturbations including outgassing and thermal recoil. Our analysis of Mercury flybys allowed us for the first time to combine BepiColombo and MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) radiometric measurements, leading to significant improvements in the modeling of the gravitational forces.

中文翻译：

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对金星和水星飞越期间获得的 BepiColombo 无线电科学和加速计数据的首次分析


ESA/JAXA BepiColombo 任务目前正在前往水星的途中，旨在揭开太阳系最内层行星的秘密。无线电跟踪测量与机载加速度计获取的数据相结合，将使航天器能够精确导航，从而实现任务的科学目标。在行星际转移轨道期间需要进行一系列行星飞越，以节省推进剂以进入水星周围的轨道。我们在这里对第二次飞越金星和前两次飞越水星期间收集的无线电跟踪和加速计测量结果进行联合分析。进行精确的轨道确定过程，以对航天器轨迹以及与动力学和观测建模相关的参数进行组合调整。加速度计数据能够检测未建模的动态扰动，包括排气和热反冲。我们对水星飞越的分析使我们首次将 BepiColombo 和水星表面、空间环境、地球化学和测距 (MESSENGER) 辐射测量结合起来，从而显着改进了引力建模。