Starwatch: the Swan soars across the midnight sky

Starwatch chart 27 August 2018

This week look out for the glorious constellation Cygnus, the Swan. It is one of the finest constellations that the northern hemisphere has to offer. It rises in the east as the night draws in, and by midnight is soaring high across the sky. Cygnus is shaped like a cross. Its great neck stretches out towards the star Albireo and back towards the tail star: Deneb (which is Arabic for tail). The wings of the swan are longer, and stretch out along a line of fainter stars. Although it cannot be seen by eye, roughly halfway between Albireo and Deneb lies Cygnus X-1, the first black hole to be identified by astronomers. The body and neck of Cygnus lie right along the Milky Way. This misty band of light can be seen from rural locations and is the combined light from the millions of stars that make up our Galaxy. In 1612, Italian astronomer Galileo Galilei described raising his telescope to the Milky Way and seeing it was composed of myriad faint stars. Deneb forms the Summer Triangle, with the bright stars Vega in Lyra and Altair in Aquila.