parsec

views updated May 23 2018

par·sec / ˈpärˌsek/ (abbr.: pc) • n. a unit of distance used in astronomy, equal to about 3.25 light years (3.08 × 1016 meters). One parsec corresponds to the distance at which the mean radius of the earth's orbit subtends an angle of one second of arc.

parsec

views updated May 29 2018

parsec (pc) Distance at which a star would have a parallax of one second of arc; equivalent to 3.2616 light years, 206,265 astronomical units, or 3.0857 × 1013 km.