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We're now going to jump over to Cygnus which appears as a very large, bright cross high in the summer sky. Cygnus' brightest star alpha Cygni has a magnitude of 1.3 and is called Deneb, which is the Arabic word for "tail". Deneb is one of the stars of the Summer Triangle.
Cygnus' most interesting star is at its other end - Albireo. Albireo is a double star. Unlike our own Sun, many if not most stars have at least one partner. These stars orbit around each other. Occasionally there will be a visual double star that consists of two stars that happen to be in the same line of sight. But Albireo is a genuine double star in which two stars are actually close to each other and they can both be easily seen through binoculars or a small telescope. What makes Albireo interesting are the colors of its two components - yellow and blue. When we talk about a red star or a blue or a yellow star we're not discussing the types of hue found in a neon sign. All stars are basically white, but they also can have a reddish or bluish tinge. It's easy to appreciate the difference of colors within Albireo, because its two stars are so close to one another and their colors are so different.
Cygnus is located in the part of the sky covered by the Milky Way.
The Planets