The Night Sky - Episode 1

DENEB-SADR in CYGNUS

This is a study of the Deneb-Sadr region in the Cygnus constellation in our Milky Way Galaxy. Watch the video below to see a tiny region of our night sky in a whole new light. And scroll on to read more about this fascinating region.

A look at the heart of one of the largest constellations in our night sky.

Here is an image of the Deneb-Sadr region in the Cygnus constellation.

To understand where in the context of the entire night sky this region is located, let us first look at the Milky Way galaxy and the Cygnus constellation.

The image above shows the Milky Way and the Cygnus constellation. Cygnus is a northern hemisphere constellation and derives its name from the latin word for swan. It is quite easy to make out the shape of a flying swan that the stars in Cygnus trace in the sky. During the summer months, Cygnus is visible all through the night.

We also see a smaller marked out region of interest containing the left half of Cygnus. This is the Deneb-Sadr region. Here is a look at the major stars in this region.

Three stars in the Cygnus constellation are clearly visible - Deneb, Sadr and ε Cygni.

Deneb is the brightest of the three. In fact, it is the brightest star in Cygnus and is also known as α Cygni. It is a blue-white supergiant, with a mass roughly 19 times that of our Sun and is estimated to be between 55,000-196,000 times as bright as our Sun.

Sadr is located at what can be thought of as the chest of the swan shaped Cygnus constellation. Not surprisingly, the nomenclature is derived from the Arabic word for chest. It is also known as γ Cygni, being the third brightest star in Cygnus, and has about 12 times the mass of our Sun. Sadr appears as a yellow-white star and is estimated to be very young - only 12 million years old.

ε Cygni is actually a multiple star system, consisting of four stars that appear as a single object to the unaided eye.

The Deneb-Sadr region also contains a number of other interesting deep space objects - notably nebulae. The image below shows the apparent locations of various nebulae.

The North American nebula is visible to the left of Deneb and is named so because it resembles the shape of the North American continent. Beside this nebula lies the Pelican nebula which when magnified resembles a, yes, pelican. The Veil Nebula Complex is a collection of multiple nebulae that are clearly visible below ε Cygni. That area hosts some beautiful structures with vivid colours on further magnification. The Gamma Cygni Nebula is located at the heart of the constellation near Sadr. Other smaller nebulae in the region include the Crescent Nebula and Tulip Nebula.

The next time you are in a place with very dark skies, try looking up and finding Cygnus and the Deneb-Sadr region.

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