Astronomy For Beginners – Dark And Reflection Nebulae

Written by Marko on September 13, 2007

“Astronomy For Beginners” theme continues discussion of nebulae. This time we take a quick look at the dark nebulae, such as Snake Nebula. The dark and reflection nebulae are gas clouds so dense that they obscure the light from background or they just block out the light of the background stars. Reflection nebulae can be seen because the light of the foreground stars bounces from the surface of the reflection nebulae. Dark nebulae can be seen because the surrounding stars provide light so much that the nebula itself simply looks “empty” (see the picture on left).Examples of the dark nebulae are Coalsack Nebula, Snake Nebula, Horsehead Nebula, Dark Horse Nebula, Pipe Nebula.

The form of dark nebulae is very irregular because they have no clearly defined outer boundaries and sometimes they take on convoluted serpentine shapes. “The largest dark nebulae are visible to the naked eye, appearing as dark patches against the brighter background of the Milky Way“. [Britannica Online].

Images of the dark and reflection nebulae can be very impressive and artistic (on the wall, for instance). Take a look at Jeff Ball’s image of Pipe Nebula.