Meanings
- uncountableastronomyThe point of a body's elliptical orbit about the moon's centre of mass where the distance between the body and the centre of mass is at its minimum.
Hence, the Earth gravity allows the decrease of the particle energy from zero to a negative value and its capture by the moon to an elliptical orbit, e.g., with a periselenium of ~2,000 km and a high aposelenium of ~70,000h km.
2004, Science and Technology Series, volume 108, American Astronautical Society, page 162Synonyms: periselene
Synonyms & antonyms
nounThe point of a body's elliptical orbit about the moon's centre of mass where the distance between the body and the centre of mass is at its minimum.
Origin
From peri- + seleno- + -ium, Latin form of -ion.
Full word history & related roots →Cite this entry
periselenium. (n.d.). In WatkinsX Dictionary. Retrieved November 3, 2026, from https://dictionary.watkinsx.com/word/periselenium
“periselenium.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/periselenium. Accessed November 3, 2026.
WatkinsX Dictionary, s.v. “periselenium,” accessed November 3, 2026, https://dictionary.watkinsx.com/word/periselenium.
Source: periselenium on Wiktionary, CC BY-SA 4.0.