The two component stars of Albireo are easily distinguished, even in a small telescope. Albireo, also known as Beta Cygni (β Cyg), is a binary star found in the constellation Cygnus, the swan. Albireo is a 3rd magnitude star and, as it is located at the head of the swan, Albireo is sometimes called the "beak star". It also forms the "Northern Cross" along with Deneb, Delta Cygni and Eta Cygni.
The name of the star first appeared in Arab text as al Minhar al Dajajah, "the hen's beak." Latin scholars misunderstood that the name had come from a kind of herb, and translated it into ab ireo. ("from ireus.") Later, people considered ab ireo as a misprint of Arabic term and transcribed it as al bireo.
When viewed with a telescope, it readily resolves into a double star, one yellow (apparent magnitude 3.1), the other blue (apparent magnitude 5.1). Separated by 34 seconds of arc, the two components provide one of the best contrasting double stars in the sky due to their different colors. The pair is located 385 light years away, and initially it was believed that the stars were merely an optical double, not orbiting around a common point as a true double star system would be. However, in spite of the large distance between them (46 astronomical unit, or about 4 billion miles), it has been shown that they are a true double system, with an orbital period on the order of 100,000 years, a rather stately and sedate dance.
The brighter, yellow member of the pair, Beta Cygni A, is itself a close binary.
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