Exospheric satellite

...An artificial satellite for the purpose of observing and investigating the environment surrounding the Earth, such as the composition and density of the atmosphere, the gravitational field, the magnetic field, and cosmic rays, as well as observing celestial bodies from outside the atmosphere. With the introduction of artificial satellites as a new observational tool, various fields of physics, such as astronomy and geophysics, have made great strides. It has become possible to directly measure the environment surrounding the Earth, such as geomagnetism and the upper atmosphere, in situ, and it has even become possible to reach planets in the solar system. In addition, astronomical observations from satellites orbiting outside the atmosphere have made it possible to observe new phenomena or to observe them with greater precision without being hindered by the atmosphere. ...

*Some of the terminology that mentions "exospheric satellite" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…大気の組成や密度，重力場や磁場，宇宙線など地球を取り巻く環境の観測･調査や，大気圏外からの天体の観測などを目的とした人工衛星。人工衛星という新しい観測手段を得て天文，地球物理といった物理学の諸分野は飛躍的な発展を遂げるに至った。地磁気，高層大気など地球を取り巻く環境をその場で直接計測することができ，さらに太陽系の諸惑星にも到達できるようになった。また大気圏外を周回する衛星からの天文観測によって，大気層にじゃまされずにより精度の高いあるいは新しい現象の観測が可能となった。…

※「exospheric satellite」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報