Parsec

A unit of distance used to describe the vast scales of the cosmos, the parsec is equal to about 3.262 lightyears, or 3.09 × 1016 meters. A star that is one parsec away would produce a parallax angle of one second of arc. A star that has a parallax shift of 0.1 arcseconds would be at a distance of 10 parsecs, and so forth.