Plasma environment around comet 67P

67P 彗星周围的等离子体环境

• 批准号: 2614478
• 金额: --
• 依托单位: Imperial College London
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2614478
• 关键词: Plasma; environment; around; comet; 67P

Unlike previous cometary missions which flew by a comet in a few hours, the European Space Agency Rosetta mission escorted comet 67P over a two-year journey, from a distance distance of 3.6 au from the Sun to perihelion at 1.2 au and to the end of mission at 3.8 au. As a result, it harvested a rich and unprecedented dataset of the neutral and plasma environment over a large range of heliocentric distance, season, latitude, longitude, outgassing and solar activity. The aim of the thesis will be to explore how the plasma environment around the comet evolved over the escort phase and to link it to remote-sensing observations. Measurements from the ion and neutral mass spectrometer will be exploited, taking advantage of the high mass resolution offered by the instrument. The evolution of ion composition over time in different interaction regions will be assessed. The findings will be compared with modelled outputs in order to infer the relative importance of chemistry versus transport and address a very puzzling question on ion dynamics. The role of collisions versus transport will also be assessed for auroral emissions, including the red line whose brightness decreases at high outgassing activity.

与以往在几个小时内飞越彗星的彗星任务不同，欧洲航天局罗塞塔任务护送67P彗星历时两年，从距太阳3.6天文单位的距离到达1.2天文单位的近日点，并在3.8天文单位结束任务。结果，它收获了大范围的日心距离、季节、纬度、经度、放气和太阳活动的丰富且前所未有的中性和等离子体环境数据集。本论文的目的是探索彗星周围的等离子体环境在护航阶段如何演变，并将其与遥感观测联系起来。将利用离子和中性质谱仪的测量，利用仪器提供的高质量分辨率。将评估不同相互作用区域中离子组成随时间的演变。研究结果将与模型输出进行比较，以推断化学与传输的相对重要性，并解决有关离子动力学的一个非常令人困惑的问题。碰撞与运输的作用也将针对极光发射进行评估，包括在高排气活动时亮度降低的红线。