perihelia
perihelium的複數形
Per·i·hel·ion Per·i·he·li·um n.; pl. Perihelia Astron. That point of the orbit of a planet or comet which is nearest to the sun; -- opposed to aphelion.
◄ ►
perihelion
n : periapsis in solar orbit; the point in the orbit of a planet
or comet where it is nearest to the sun [ant: aphelion]
[also: perihelia (pl)]