apsis

[prettygoodword]

apsis - n., (Astron.) one of the two points in an elliptical orbit when the orbiting body is nearest (periapsis) or furthest (apopsis) from the center of attraction; (Arch.) an apse.


For bodies orbiting Earth, these have the special names perigee and apogee; around the Sun, perihelion and aphelion. You can substitute other body names, but these are more rarely used; Wikipedia has a helpful list anyway. From Latin apsis, arch, vault, from Greek hapsis, from haptein, to fasten.

---L.

Comments

[packbat.livejournal.com]

Sweet! (I keep forgetting that the -gee and -helion forms are specific to those two bodies...)

[prettygoodword.livejournal.com]

It took me a couple years, when I was younger, to get straight what, exactly, the -gee and -helion forms refered to. After much confusion.

---L.