One of the most popular night sky objects for amateur astronomers is the star Albireo located in the constellation Cygnus the swan.
To the human eye Albireo is just another faint star among several thousand in the cool summer and fall evenings. A small telescope will split Albireo into two separate stars. That alone would make Albireo stand out but it offers one more surprise. The colors of the two stars are in stark contrast to each other. One is a dimmer blue the other is a bright golden color. The colors represent each stars temperature, blue being the hottest, while the gold cooler.
For years Albireo has been classified as a binary star, where both stars are close enough to orbit each other. For amateur astronomers the idea that these two stars could be actual doubles makes them even more interesting to view. Recent observations by the Gaia mission has thrown doubt on this and seems to show the two are not true binaries but just an alignment and really too distant to be gravitationally bound. Some think the Gaia data has some errors. So determining if the two are true binaries or optical doubles is debatable. But even if they are not true double this does not decrease the enjoyment viewing these colorful stars.
Albireo can be found in the popular summer constellation Cygnus the Swan. It marks the head of the Swan, opposite the bright star Deneb which marks the tail of the swan. The constellation is also known as the Northern Cross where Deneb is the top of the cross and Albireo is the bottom. It is found high overhead in August and September.
This is one set of stars you cannot afford to miss.
