If we look at orbital mechanics, we can find great tables like these, demonstrating the name of the periapsis and apoapsis around various celestial bodies:
Objects Periapsis Apoapsis Galaxy Perigalacticon Apogalacticon Black hole Perimélasma Apomelasma Star Periastron Apoastron Sun Perihelion Aphelion Mercury Perihermion Apohermion Venus Pericytherion Apocytherion Earth Perigée Apogee Moon Periselene Aposelene Mars Periareion Apoareion Jupiter Perizene Apozene Saturn Perikrone Apokrone Uranus Periuranion Apouranion Neptune Periposeidion Apoposeidion Pluto Perihadion Apohadion
(table from How do apsides of celestial bodies get their names?)
My question is why? Why have so many composite names? Are there a few standard justifications for why such naming is useful?
I ask my question from a linguistic perspective. Obviously the real reason why it is done this way is because this is the way it is done. However, often in linguistics, we can come up with "reasons" for why things are done. For example, in mountain climbing, we see vocal calls between two climbers like "on belay" "climbing" "climb." One of the justifications for these terms is that they have different numbers of syllables: 3-2-1. Obviously it is very bad news if, in bad windy conditions, you mistake one instruction for another, and it may be that the number of syllables you hear is all the information you get! We see similar in the military, where language forms patterns that can withstand the din of combat.
Is there a reasonably accepted justification (or a few common justifications) for why we have so many terms for the periapsis and apoapsis? Or is it just the way it is done?