The Summer Triangle is still high in the sky throughout September, giving an ideal view of the 16th largest constellation — the majestic Cygnus, the swan who takes flight, nose first, down the Milky Way. Deneb, one of the three stars of the Summer Triangle, translates to tail. The blue-white supergiant star is the tail-end of the swan.

The double star Alberio, known as the “beak” star, marks the swan’s beak. To the naked eye, Alberio appears as a single star, but through a small telescope, it’s easy to observe color variations of two stars. The brighter of the two stars appears yellow, while the fainter of the binary system is blue. Alberio also marks the base of the asterism known as the Northern Cross. Deneb is at the top. To one side of the Milky Way is the star Gienah, and on the other, Rukh, configuring the edges of the cross. The brightness of the stars makes this asterism easily recognizable.

Within the Cygnus constellation is the famous Cygnus X-1, a galactic x-ray source. The elegant Veil Nebula is also located within Cygnus, which is worth a look in a dark sky.

Another constellation worth searching for is Delphinus the dolphin, which swims between Cygnus and Aquila the eagle, just to the east of the Summer Triangle. Its star pattern appears to represent a tiny cavorting dolphin.

First Published: September 15, 2020, 11:00 a.m.