Nebula
A nebula is a giant cloud of gas (mostly hydrogen and helium) and cosmic dust situated between stars in the interstellar medium. Nebulae serve as sites of stellar birth and death—including emission nebulae that glow from ionized gas, reflection nebulae that scatter starlight, and dark nebulae that obscure background stars.
Source: science.nasa.gov
APODs including "Nebula"
In the Center of the Dumbbell Nebula
13/10/1998
Here's part of the Dumbbell Nebula that you can't see through binoculars. To see this, we suggest a sophisticated spectrograph attached to a telescope with an 8-meter aperture. Pictured above is the central part of the Dumbbell Nebula, also known as M27 and NGC 6853. The Dumbbell is a planetary nebula created by the aging bright star visible just right of center. The nebula, located in the constellation Vulpecula, is thousands of years old. Visible in this false-color photograph is glowing hydrogen gas (green) and enigmatical globules of dense molecular gas and dust (red).