Perseus is found in the Milky Way, which means that the skies here are replete with glittering background stars, wonderfully seen in binoculars. The hero Perseus is represented as holding the severed head of Medusa, the Gorgon. The constellation contains one of the most celebrated of variable stars (Algol) as well as several very fine deep sky objects -- the famous Double Cluster and M34.
Alpha Persei, Mirfak (The Elbow) or Algenib (The Side), although this latter name is also the designation for gamma Pegasi. This particular region of the sky is very rich and a marvelous sight in binoculars. Mirfak is one of four stars which form a circular line around Cassiopeia. First find Cassiopeia then locate the three stars in Andromeda. Further along this outer group and you'll find Mirfak. Of course you'll have to adjust the veiwing angle depending on where Cassiopeia is found. Once you've located Mirfak, you'll easily discover Algol (beta Persei) by moving away from the Pole Star (that is, due south) about ten degrees.
Beta Persei is Algol, one of the most notable of variable stars. Perseus is represented here holding the head of the Gorgon Medusa, whose head he has just severed. One look from the Gorgon's evil eye and the victim was dead. Algol, ‘The Demon’, represents the sparkling eye of Medusa. The name indicates that the ancients also knew that the star shone with a variable magnitude. Algol is the prototype of an important type of variable known as the eclipsing variable. Two close stars orbit each other, with the visual magnitude changing as they block out each other's light. In Algol's case, these eclipses happen every 2.9 days, with the star's visual magnitude fluctuating between 2.2 and 3.5, a very noticeable difference. This minimum lasts about ten hours before the maximum magnitude is again reached. Algol is quickly found by first locating Mirfak. Now move opposite to the Pole Star (due south) ten degrees.
Eta Persei is an orange supergiant with a blue companion, suitable for small telescopes. The star is northwest of alpha Persei and is convenient for locating the Double Cluster First hop up to gamma -- just northwest of alpha, barely out of the same FOV. Now placing gamma in the lower left of your glasses brings eta into view. Northwest of eta, about seven degrees, is the famous Double Cluster.
