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This famously colorful and easy-to-split double star is now high in the east a few hours after dark. What colors do you see?
The Summer Triangle is now well above the horizon before midnight. That means Albireo, the head of Cygnus the Swan, is also visible. It’s a great double star with contrasting colors. Credit: Stellarium
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Look east around 11 P.M. local daylight time, and you’ll see three bright stars forming a triangle — this is the famous Summer Triangle asterism, which flies high overhead in the middle of short summer nights. We’re still a bit early for that, but with all three stars — and their constellations — above the horizon, it means we can now enjoy all these star patterns have to offer. Tonight, we’re after not Deneb, the tail of Cygnus the Swan, but the long-necked bird’s head to Deneb’s southwest: Albireo.
Glowing at magnitude 3.1, Albireo (also cataloged as Beta [β] Cygni) is a famous double star that is easy to split in small scopes and even well-stabilized binoculars. Its two component stars shine at magnitude 3.4 and 5.1, separated by some 34”. But what really catches the eye are their colors: the brighter star appears yellow-gold, while the fainter component shines with a much bluer light. However, no two pairs of eyes are the same. Some observers see blue and white, while others even see yellow and green (although this is a trick of the brain — there are no green stars!). What colors do you see?
Sunrise: 5:32 A.M.
Sunset: 8:26 P.M.
Moonrise: 12:28 A.M.
Moonset: 11:04 A.M.
Moon Phase: Waning gibbous (63%)
*Times for sunrise, sunset, moonrise, and moonset are given in local time from 40° N 90° W. The Moon’s illumination is given at 10 P.M. local time from the same location.