You searched for: “arc second
arc minute, arc second
Units for measuring small angles, used in astronomy.

An arc minute (symbol ') is one-sixtieth of a degree, and an arc second (symbol ") is one-sixtieth of an arc minute. Small distances in the sky, as between two close stars or the apparent width of a planet's disk, are expressed in minutes and seconds of arc.

This entry is located in the following unit: Astronomy and related astronomical terms (page 3)