This is the 7982nd most frequent Japanese word.
大気圏
"大気圏" means "atmosphere" or "atmospheric layer."
In this sentence, 大気圏 denotes the space of Earth's atmosphere where human activity typically occurs.
私たちの日常生活は大気圏の中で行われます。
Our daily life takes place within the atmosphere.
Here, 大気圏 refers to the Earth's atmosphere as a boundary dividing the Earth from outer space.
人工衛星は大気圏外を飛行します。
Satellites fly outside the atmosphere.
In this instance, 大気圏 describes the atmospheric layer that spacecraft enter during re-entry to Earth.