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Cassiopeia - Queen of the Night


Mythology - Cassiopeia was the vain and beautiful Queen of Philistia (Ethiopia). She once claimed to be more beautiful than the Nereids or sea-nymphs, and when Poseidon heard this her punishment was the sacrifice of her daughter, Andromeda, to the sea monster Cetus. After her daughter was saved and promised to Perseus as his wife, Cassiopeia plotted with her daughter's fiancée Agenor, to kill Perseus. While outnumbered and attacked at his wedding feast, Perseus pulled Medusa's head from his bag and transformed Cassiopeia, Agenor and his men to stone. The Queen and King Cepheus are depicted in the sky facing each other's feet. They cannot speak to each other. Because the Queen insulted the sea-nymphs, the pair never set below the surface of the sea. The constellation's name is derived from a Phoenician phrase that means the Rose-Colored Face.
Stars - Gamma cassiopeiæ is an irregular eruptive variable which normally hovers around mag. 2.2. It brightened to 1.6 in 1937 and faded to 4.0 by 1940. It could be ready for another outburst soon! RZ cassiopeiæ is an eclipsing binary system which fades from its normal mag. 6.4 down to 7.8 over 2 hours and then back again every 29 hours. You should be able to follow this over two successive nights through binoculars.
Deepsky - Cassiopeia contains many clusters (49 actually!) all of which are open or galactic clusters. The following are good binocular objects: NGC 225, NGC 663, NGC 457 (bright and contains 100 stars), M103
(contains about 40 stars), M52 (a large scattered cluster of young blue stars) and NGC 7789 (contains
roughly 1000 members and looks like a dull misty patch through binoculars)
Visibility - Cassiopeia is visible all year round, though the best time to see her is in the Autumn when she is high overhead.