A
square degree (
deg2) is a non-
SI-compliant
unit measure of
solid angle. Other denotations include
sq. deg. and
(°)². Just as
degrees are used to measure parts of a circle, square degrees are used to measure parts of a
sphere. Analogous to one degree being equal to p / 180 radians, a square degree is equal to (p / 180)
2, or about 1 / or 3.0462
steradian (0.30462 msr).