Astr110 Photography Projects, Fall 2006

Swan Nebula (M17), Jodi Unema

The Swan Nebula, also known as M17, the Omega Nebula, the Horseshoe Nebula, or the Lobster Nebula, was discovered in 1745-46 by Philippe Loys de Chéseaux.  The discovery was not well known, however, and in 1764, Charles Messier rediscovered and cataloged it.  This emission nebula, or cloud of gas and dust that emits light, has about 35 stars hidden inside of it, causing it to glow brightly.  The Swan Nebula, which can be found in the northern part of the constellation Sagittarius, has a mass that is 800 times that of the Sun.  This beautiful phenomenon can be seen by the naked eye on a clear night. 
           
The dominant reddish or pink color in this nebula is caused by hot hydrogen gas shining in the newly formed stars of the nebula.   M17 also contains a lot of dark material, seen on the right side of the picture, which is actually a layer of dust that blocks the view of many stars behind it.  It may look like the nebula stops with the red color, but it actually continues through what looks like open space.  The young stars in the nebula have heated up this dust, and it will shine brightly in infrared light.  The Swan Nebula extends outside of this picture’s boundaries to over 30.54 light years across, as it has an angular size of over twenty-one arcminutes. This colorful nebula displays God's creativity and gives us a better understanding of his creation.

References:
Perkins, Philip . "M17-Swan Nebula-Sagittarius ." Astro Cruise. <http://www.astrocruise.com/m17.htm>.

Frommert, Hartmut and Kronberg, Christine. "Messier 17 ." Students for the Exploration and Development of Space. <http://www.seds.org/messier/m/m017.html>.