Apo and peri

[KvickFlygarn87]

I've never quite understood, what's with the different apo- and peri- suffixes? For example, Apogee and perigee, aphelion and perihelion.

Does it differ in some sort of condition?

Sphere of Influence?

[Kryten]

It's to do with the body they're relative to; Apogee-earth, Apohelion-sun, Apoapsis-generic term, et.c.

[KvickFlygarn87]

Ah, thanks! Mods may close this proof of stupidity now.

[astropapi1]

Apokee-Kerbin.

Love your sig.

[KvickFlygarn87]

I love it too.

P.S. derail'd.

[K^2]

These come to us from Greek via a some other languages. In Greek, Earth is Γη (Gi), hence apogee means furthest point (along orbital path) from Earth. Similarly, Ήλιο (ÃÂlios) is the Sun. So we have aphelion to denote the part furthest from the Sun. Same deal with perigee and perihelion, but these denote the closest point. In principle, if you know the Greek name of the object, you should be able to construct the proper term for the apoapsis and periapsis of this particular body.

[Nuke]

Apokee-Kerbin.

Love your sig.

i usually use apokerb

[Idobox]

If I had to give a Greek name to Kerbin, it would be Hephaistos, the ugly god of forges, volcanoes and artisans. Cause my crafts are ugly as hell, require a lot of craftsmanship, and often in beautiful explosions with debris flying everywhere.

[K^2]

Hm. He was the guy that Prometheus stole the fire from, wasn't he? I don't think it'd fit. If I recall correctly, he strove for perfection in his works. Not very Kerbal of him.