A parsec is a unit of distance used in astronomy, equivalent to approximately 3.26 light-years. To be more precise, one parsec is about 3.086 x 10^13 kilometers (or 1.917 x 10^13 miles). It is defined as the distance at which one astronomical unit (the average distance between the Earth and the Sun) subtends an angle of one arcsecond. This unit is particularly useful for measuring distances to stars and galaxies beyond our solar system.
