2012-07-18

prettygoodword: text: words are sexy (Default)
2012-07-18 07:11 am

perilune / apolune

perilune (PER-i-loon) - n., the point in a lunar orbit that is nearest to the moon.

apolune (AP-uh-loon) - n., the point in a lunar orbit that is furthest from the moon.


The two apsides when the body orbited is the moon -- there are terms specific to many other bodies. Also sometimes called periselene and aposelene in order to avoid mixing Greek and Latin roots -- namely, peri- from perí, adv. and prep. meaning near/about and apo- from apó, verbal prefix meaning away/apart + luna, moon. Coined in the late 1960s as part of the Apollo program, fwiw.

---L.