The seventh-largest constellation, lying in the northern sky, and representing the winged horse of Greek mythology. The stars Markab (Alpha Pegasi), Scheat (Beta Pegasi), and Algenib (Gamma Pegasi) form three corners of the Square of Pegasus, which is completed by the star Alpheratz (Alpha Andromedae) from neighbouring Andromeda. Enif (Epsilon Pegasi) is a double star. M15 is a 6th-magnitude globular cluster.
Subjects: Astronomy and Astrophysics.