Parsec Parsec The parsec (symbol: pc) is a unit of length used to measure large distances to astronomical objects outside the Solar System. A parsec is defined as the distance at which one astronomical unit subtends an angle of one arcsecond, which corresponds to astronomical units. One parsec is equal to about 3.26 light-years (30 trillion km or 19 trillion miles) in length. The nearest star, Proxima Centauri, is about from the Sun. Most of the stars visible to the unaided eye in the night sky are within 500 parsecs of the Sun. The parsec unit was probably first suggested in
26 Miles (Santa Catalina) "Forty kilometres in a leaky old boat . . .", a rare mention of a metric unit in American popular music, and a tolerably accurate conversion (26 miles = 41.8 km). 26 Miles (Santa Catalina) "26 Miles (Santa Catalina)" is a popular song by the 1950s and 1960s pop band The Four Preps. It reached number two on the "Billboard" Hot 100 and number six on the "Billboard" R&B chart in 1958. The song sold over a million copies and the group appeared on several television shows, including "The Gisele MacKenzie Show" (March 15, 1958) and "The Ed Sullivan Show".