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Summer Triangle marks seasons from spring to winter

Deneb. (Flickr Photo/JP Stanley)

As we reach start of the summer season, I thought it would be important to share some of the secrets of the brighter stars of the summer season, as well as the details of these amazing stars.

Many of you may be aware of the large triangle of stars that we refer to as the Summer Triangle.

Rising high in the east northeast sky during these hot summer nights, we find three main stars that are easy to view with the naked eye.

These stars are named Vega, Deneb and Altair and they are located in some of the most interesting constellations in the night sky.

Vega is located in the constellation of Lyra, the harp, while Deneb is located in the constellation of Cygnus, the swan.

The last star, Altair, is located in the constellation of Aquila, the eagle.

The brightest of these three stars is Vega, a hot blue star some 25 light years from the sun.

Vega was the pole star, around 12,000 B.C. and was the first star to be photographed, other than the sun, back on July 17, 1850.

Vega is 2.1 times as massive as the sun and rotates very rapidly around its axis. When we view Vega in a telescope, the star is seen pole on to our line of sight.

The light from Vega left the star in 1996 and is just arriving at your eye tonight.

Here is what Vega looks like.

The second-brightest of the Summer Triangle of stars is Altair.

Altair is located some 16.7 light years from the sun and located in the constellation of Aquila.

Altair is a hot blue white star, which is spinning so fast, the star is actually elliptical in shape and rotates in a period of nine hours.

Altair is 1.8 times the mass of the sun.

Amazing as it may seem, Altair is one of the few stars to have its image captured by a large telescope.

Here is what Altair looks like.

Finally, the faintest star of the Summer Triangle is actually a most massive blue super giant star Deneb.

Deneb is located at the tail end of the Cygnus constellation.

It has a luminosity of well over 100,000 times that of the sun and is located well over 2,500 light years from the sun.

Deneb is actually one of the most luminous stars in the entire Milky Way galaxy and is obscured by dust in the interstellar medium.

Here is how massive Deneb is relative to our sun.

Here is how to find the Summer Triangle.

On a final note, if the star Deneb were at the distance of Vega, we would have a most interesting situation.

If that were the case, Deneb would shine well over 15 times the brilliance of Vega and cast shadows on Earth.

To print your own monthly star chart, click here.

To view satellites/dates/times of passage, click here.

Listen to the Dr. Sky Show on KTAR News 92.3 FM every Saturday at 3 a.m.

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