Reflection nebula are light reflections. Usually caused by a pairing of two key things: stars and nearby dust, reflection nebula are most frequently blue in color, however they can also be orange, yellow, or reddish, depending on the color of the starlight being reflected. Reflection nebula are usually fairly small, however Orion Nebula, the Great Nebula, is one of the largest in the sky (and it so happens to also be comprised of emission nebula and dark nebula as well.)
Dark nebula are light absorbers, patches and filaments and swaths of dust, often forming gigantic dust lanes in our galaxy. Formed of black body particles…dust, of any range of variety, permeate our galaxy and other galaxies. The dust of dark nebula are generally the medium that gives rise to reflection nebula, as the dist reflects the light of nearby stars. Dark nebula are often invisible to the astronomer, as they frequently exist in regions of our galaxy backed by the blackness of interstellar and even intergalactic space. Dark nebula are usually revealed by the light behind them…the densely packed stars of the milky way, or that of a nearby nebula set behind.
Currently no dark nebula images.
SNRs & Planetary Nebula
Planetary nebula are interesting and usually quite unique objects in space. Frequently forming bubble shapes, often whispy and usually ill-defined, sometimes measurably fluctuating in size and shape over relatively short periods of time (often a matter of mere years), planetary nebula are usually thought to be the remnants of stellar explosions, or supernova remnants (SNRs)…but could also be caused by other forces.
Currently no planetary nebula images.