Pegasus is a distinctive northern constellation that is named after the Winged Horse in Greek mythology. Only the top half of the horse is depicted in the constellation. Pegasus is easily found in the sky by locating the four bright stars in the great square of Pegasus, an asterism formed by Alpha Pegasi (Markab), Beta Pegasi (Scheat), Gamma Pegasi (Algenib), and Alpha Andromeda (Alpheratz). Alpheratz was once also designated as Delta Pegasi, but that designation is no longer used. The nose of Pegasus is marked by Enif (Epsilon Pegasi), the brightest star in the constellation at magnitude 2.38. The spectral-class K orange supergiant is located 690 light-years away. Pegasus was cataloged by the Greek astronomer Ptolemy in the second century C.E. (Common Era). It is the seventh largest of today's 88 modern constellations, covering 1,121 square degrees of sky.