Near Cassiopeia is the constellation of Perseus, which has a “V” shape and is formed by closely packed stars. Like its neighbor Cassiopeia, Perseus is also located in the Milky Way.
In Greek mythology, Perseus is the son of Zeus and Danae. When Perseus was a child, he was placed in a box and tossed into the sea by a cruel grandfather, then was rescued by some fisherman. Later Perseus rescued Andromeda from sea serpents, and also had a big adventure with Medusa. Medusa is known for having snakes as hair and for turning people into stone simply by making eye contact with them.
Perseus was asked for Medusa’s head as a wedding gift by King Polydectes. The king was in love with Perseus’ mother Danae and he thought this would be a convenient way to get rid of her son. The gods Athena and Hermes provided some much needed assistance to Perseus and he did manage to cut off the head of Medusa and brought it back to the wedding party of King Polydectes. He then used it to turned all the guests into stone.
Algol – The Demon Star
Medusa’s head is represented within the constellation by the star beta Perseus, also known as Algol. It is the most famous variable star in the sky. Normally, the start has a magnitude of 2.2, but every 2.867 days, Algol suddenly dims down to a magnitude of 3.5. The period of dimming and the subsequent period for Algol to resume its usual brightness together last about five hours and it makes it a very interesting start to monitor.
Algol is actually two massive stars, one being smaller but brighter than the other. When we on Earth see Algol suddenly dim, it’s because the slightly larger and much dimmer star has moved into a position between the brighter star and us. When it brightens up again, it’s because the larger dimmer start has moved behind the brighter star.
Algol has mythology of its own and is associated to the devil. The arabs call it “Ras al-Gul” which means the “Ghoul’s Head”. Algol has also been called the Demon Star and the Blinking Demon. The Jews have referred to it as “Rosh ha-satan” which translates to Satan’s Head. The Chinese called it “Tseih She” which means the Piled up Corpses.
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Orion SkyQuest XT6 Dobsonian Telescope
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