Nebulae represent clouds of gas and dust which appear as hazy or fuzzy objects when viewed through a telescope and are characterized as one of four types (emission, planetary, reflection or dark). Emission nebulae, such as the Lagoon nebula (M8), simply glow, for example, with a stunning shade of red. Planetary nebulae appear as small greenish disks through a telescope, thus emulating the planets Uranus and Neptune, as a result of gas masses being thrown off by dying stars (ex. M27, Dumbbell nebula) or represent supernova remnants (ex. M1, Crab nebula). In contrast, reflection nebulae are characterized with gas surrounding young stars which reflect the stellar light (ex. M45, Pleiades) and, thus, yield beautiful images of nebulosity. Finally, dark nebulae are detectable and studied only using parts other than the visible spectrum and are believed to be associated with the formation of stars (ex. M16 in Serpens).

Note: NGC 6514 in Sagittarius is more commonly referred to as the Trifid Nebula owing to its three-lobed appearance and is one of the relatively few examples where a nebula is characterized as both emission and reflection thanks to the H-II emission nebulosity which dominates the field of view and which is accompanied by reflection nebulosity as well to the north. The emission nebulosity is illuminated by a central triple star system involving O stars ranging in magnitude from 7.6 to 10.7. The Trifid Nebula lies 2,200-7,600 light-years away (depending on the source) with 5,200 light-years being the most commonly cited estimate. The dark lanes which bisect the three lobes were catalogued by EE Barnard in his study of dark nebulae (as B85) whereas recent studies have discovered a stellar nursery involving over 100 young stars and at least one Herbig-Haro object (HH339). NGC 6514 was first detected by Charles Messier in 1764.

Note: The result below will require a repeat visit and under (much) better seeing conditions.