This is a systematic attempt to identify and assess near-equatorial, high-eccentricity orbits best suited for studying the Earth’s magnetosphere, in particular its most dynamic part, the plasma sheet of the magnetotail. The study was motivated by the design needs of a multi-spacecraft “constellation” mission, stressing low cost, minimal active control and economic launch strategies, and both quantitative and qualitative aspects were investigated. On one hand, by collecting hourly samples throughout the year, accurate estimates were obtained of the coverage of different regions, and of the frequency and duration of long eclipses. On the other hand, an intuitive understanding was developed of the factors which determine the merits of the mission, including long-range factors due to perturbations by the Moon, Sun and the Earth’s equatorial bulge.

中文翻译：

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系统确定磁层飞行任务首选轨道的方法：1.单颗卫星

这是一种系统性的尝试，旨在识别和评估最适合研究地球磁层，特别是其最动态部分的磁尾等离子体片的近赤道，高偏心度轨道。这项研究是出于对多航天器“星座”任务的设计需求的推动，强调低成本，最小的主动控制和经济的发射策略，并在数量和质量两方面进行了研究。一方面，通过全年收集每小时的样本，可以准确估算出不同区域的覆盖范围以及长食的频率和持续时间。另一方面，人们对决定飞行任务优劣的因素有了直观的了解，包括由于月球，太阳和地球赤道隆起的扰动引起的远距离因素。