The Summer Triangle part 3 Deneb
Deneb is the faintest of the summer triangle of stars. It is in the constellation of Cygnus the Swan but it is sometimes known as the Northern Cross for obvious reasons. The name Deneb comes from the Arabic ‘The Hen’s Tail’ In mythology Cygnus was always associated with a bird, the most celebrated legend concerns one of the many dubious adventures of Jupiter or Zeus.
Deneb although appearing fainter than Altair or Vega is much further away. It is about 1,500 light years away. The light that reaches us this summer left around the time ‘dark ages’ began in Europe around 500 AD. Deneb is about 70,000 times as luminous as the Sun. It is of course much hotter than the Sun. If Altair, Deneb and Vega were all the same distance away Deneb would appear like a searchlight in the sky.
Cygnus lies in a part of the Milky Way which is our galaxy and even without a telescope and away from city lights it is possible to see the many faint stars that form the Milky Way.