How to Recognize the Constellation Cygnus in the Night Sky

Cygnus, the swan, is a constelation that can be observed in the northern hemisphere during summer and autumn. Cygnus reaches its highest position in the night sky at about 9 p.m. during the month of September. The swan forms part of an asterism known as the Northern Cross, and is bordered, in the night sky, by the constellations Draco, Lyra, Lacerta, Cepheu, Vupecula and Pegasus. Cygnus is represented in the sky by Deneb as the tail, Albireo as the beak and Delta and Epsilon Cygni as the wings of the swan. Deneb, which is the brightest star in this asterism, forms part of the summer triangle along with Altair in Aquila and Vega in the constellation Lyra.

Major stars in the constellation Cygnus   

The most prominent stars giving form to the Swan are Deneb, Albireo, Gienah, Sadr and Delta Cygni. Deneb is a blue and white supergiant star of magnitude 1.3. Deneb is also the brightest star in Cygnus. Albireo is a binary system formed by a blue star of magnitude 5.i and an orange star of magnitude3.1. Geniah is an orange giant star of magnitude 2.5. Sadr is a yellow supergiant star of magnitude 2.2 and Delta Cygni is a binary system formed by a giant star of magnitude 6.6 and a blue-white giant star of magnitude 2.9. Cygnus is situated in the plain of the Milky Way; therefore, there are many visible stars in the neighborhood of this constellation.

Deep sky objects in Cygnus

Due to its position in the plain of the Milky Way, there are a number of star cluster and nebulae in the vicinity of Cygnus. M30 (NGC 7092) is an open cluster of about 30 stars. M39 is an open cluster of about 30 stars, some of which are of magnitude 7. NGC 6910 (the Rocking Horse Cluster) is another open cluster of 16 stars of 7 magnitude. Dolidze 9 is a faint open cluster of more than20 stars. Dolidze 9 is a faint open cluster with more than 20 stars. Collinder 421 is an open cluster of more than 30 stars. Berkeley 90 is a small open cluster with more than 16 stars. All of these open clusters appear to be embedded in  nebulosity.

The North America nebula (NGC 7000, named like that because it resembles the North American continent, is an emission nebula with an apparent magnitude of 4 and extending about 2 degrees across in the night sky. The Pelican Nebula is an emission nebula located near the bright star Deneb. Cygnus X-1 is an X-ray source which is thought to be caused by a black hole accreting matter in a binary system. Cygnus A is a powerful radio galaxy. Its activity is due to a supermassive black hole, accreting matter at its nucleus. A number of extra solar planets have been discovered in Cygnus; one of the most outstanding is Kepler 22b, which was one of the first Earth-like planets discovered.

How to identify Cygnus in the night sky

The best way to identify the constellation Cygnus is by locating other landmarks around its vicinity. One of the most prominent landmarks is a triangle of stars formed by Altair in the constellation Aquila, Vega in Lyra and Deneb in Cygnus. These three stars form a right triangle known as the summer triangle. Vega is the brightest star in the triangle and can be easily spotted during a night clear sky. Altair, which is the second brightest star in the summer triangle, is towards the south and east of Vega and Deneb, which is the third brightest star in the triangle, is in the northeast region from Vega.

During clear night skies and away from light polluted cities, Cygnus can be seen lying in the plain of a hazy, band known as the Milky Way Galaxy. Within this region, there are a number of deep night sky objects, such as star clusters and nebulae. Deneb, which lies in the region of an asterism known as the Northern Cross, has stopped the fusion of hydrogen within its core and is predicted to explode as a supernova within the following few million years. According to seds.org, Cygnus, the swan, along with Aquila, the eagle and the Vulture, nowadays Lyra are representations of the Stymphalian Birds.

Cygnus, the swan, is a constelation that can be observed in the northern hemisphere during summer and autumn. Cygnus reaches its highest position in the night sky at about 9 p.m. during the month of September. The swan forms part of an asterism known as the Northern Cross, and is bordered, in the night sky, by the constellations Draco, Lyra, Lacerta, Cepheu, Vupecula and Pegasus. Cygnus is represented in the sky by Deneb as the tail, Albireo as the beak and Delta and Epsilon Cygni as the wings of the swan. Deneb, which is the brightest star in this asterism, forms part of the summer triangle along with Altair in Aquila and Vega in the constellation Lyra.