Milky Way constellations Cassiopeia and Perseus


Queen Cassiopeia is the wife of Cepheus. She's represented as being chained upside down to her throne in the sky as punishment for boasting that her daughter Andromeda was more beautiful that the daughters of the sea god Nereus.

The gods became angered and sent a sea monster to destroy the coast of Cassiopeia and Cepheus' kingdom. Not wanting the coast destroyed, Cassiopeia sought help from Zeus, King of the gods, who advised her to offer her daughter as a sacrifice. Andromeda sat on a rocky ledge waiting for the sea monster to devour her when Perseus rode out of the sky on his winged horse, Pegasus, and rescued her. They fell in love and were placed next to each other among the stars.

Cassiopeia is the "W" that's visible all year as it circles the North Star Polaris. Currently, it's high in the northeast. Perseus the Hero sits just below her in the sky. It's a large constellation in the shape of a man with a triangular shape body with legs, that's viewed sideways.

Of its 14 stars, six are very bright. The brightest star, Mirfak, is a yellow white super giant. It's in his lower left body where his leg begins. Blue-white Algol, the Ghoul Star, is to the right of Mirfak anchoring the other side of his body. It's also depicted as the head of the Gorgon he kills.

Algol is an eclipsing variable that dims for 10 hours every 3 days. It's actually a multiple star system with three stars that spin around each other changing its brightness. For a long time, no one knew why its brightness changed, so it was called the Ghoul Star.

Perseus, the half-mortal son of Zeus, is one of the more prominent Greco-Roman heroes. He went into battle with the Gorgon Medusa, who would turn any person into stone. Perseus used the shield as a mirror to avoid her glance. When he lopped off her head the winged horse Pegasus was born of the blood, and Perseus took the horse as his own. He then used Medusa's head as a weapon to rescue Andromeda from the sea monster Cetus, who was then turned into stone.

Between Perseus and Cassiopeia are twin star clusters NGC 869 and 884, which are just above his upper right arm. With the naked eye they look like a bright knot, but with binoculars you can see the beautiful stars. These are dense star clouds with many young blue and white stars. They are at the heart of Merlotte 20, a large cluster of stars scattered over the Milky Way. It looks like a large hazy patch.

Autumn begins on the 22nd, and it usually gives us pleasant weather and great night sky viewing. Now that the new moon is on the 25th, the skies will be dark. So go out and enjoy viewing our magnificent sky.

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