noun, noun which may take the genitive case particle 'no'
outside Earth's atmosphere; outer space; exoatmosphere
Refers to the region beyond Earth's atmospheric envelope. Used in scientific and technical contexts, as well as in general descriptions of space.
Outside Earth's atmosphere, sound does not travel because there is no air.
The satellite orbits in outer space.
大気圏 refers to the atmosphere itself, while 大気圏外 refers to the region outside it.
宇宙空間 is a broader term for outer space, while 大気圏外 specifically emphasizes being outside the atmosphere.
Compound of 大気圏 (atmosphere) + 外 (outside). The exact historical derivation is uncertain; the spelling is conventionally associated with the meaning 'outside the atmosphere'.