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A Field Book of the Stars/Cassiopeia

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CASSIOPEIA (kas-i-ō-pē'-ya)— THE LADY IN THE CHAIR. (Face North.)

Location.—A line drawn from (δ) Ursæ Majoris, through Polaris, strikes (α) Cassiopeiæ. It is situated the same distance from Polaris as Ursa Major, and about midway between Polaris and the zenith in the Milky Way. Cassiopeia is characterized by a zigzag row of stars which form a rude "W," but in mid-autumn, to an observer facing north, the "W" appears more like an "M," and is almost overhead. Note the spot marked 1572. This is where a very famous temporary star appeared in that year. It was bright enough at one time to be seen in full sunshine. The star (η) is comparatively near to us, its light taking not much over twenty years to reach us. Caph is almost exactly in the equinoctial colure, or first meridian. It is 30 degrees north of (α) Andromedæ, with which and the Pole Star and (α) Pegasi it forms a straight line.

Caph is equidistant from the Pole, and exactly opposite the star Megres in Ursa Major; with (α) Andromedæ and (γ) Pegasi it marks the equinoctial colure. These stars are known as "The Three Guides."

The chair can be readily traced out, bearing in mind that β, α, and γ form three of the four corners of the back, and δ and ε, one of the front legs. The word "Bagdei," made up of the letters for the principal stars, assists the memory.

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