The North America Nebula and Sadr region (IC1318)
Alqueva´s Dark Sky Reserve | Best Of | by Year: 2013 | Stars and Constellations
In this deep sky wide field view taken with a 70mm lens, we could appreciate a sky of endless colored stars, surrounding The North America Nebula (NGC 7000), an emission nebula in the constellation Cygnus, close to Deneb (the blue brightest star in the image center). At its right, we also could see the Sadr region, or IC 1318, a diffuse emission nebula surrounding Sadr or Gamma Cygni star (the second brightest star in the picture).
But why we can find this colorful diversity of stars ? “Astronomers came to understand that bluer stars are intrinsically brighter because they are more massive than white or red stars, and more massive stars burn much faster and hotter than less massive stars. The bluish type-O stars, for example, are only 30-50 times more massive than yellow-white stars like our sun. But O stars burn a million times brighter, so they have far shorter lifetimes. O and B stars only last a few million years before they die in spectacular supernova explosions, while cooler and less massive K and M stars burn steadily for billions of years”. Canon 60Da – ISO1600; 70mm f/4 Exp. 119 secs. + Vixen Polarie mount travel. In 5/07/2013 at 3:30 AM (sinlge frame).
