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messier 8 widefield

 

Looking towards the center of the Milky Way gives us a unique perspective into the complexity of the galaxy in which we live. The Lagoon and Trifid Nebulae dominate this intriguing image, while a myriad of other deep sky objects lie scattered about the field. Large quantities of interstellar gas and dust are literally intertwined throughout this entire area of the sky, giving it a somewhat chaotic appearance. When such clouds are located near a hot enough star, the intense ultraviolet radiation from the star will ionize the gaseous portion of the cloud and cause it to fluoresce with the ruddy glow of hydrogen-alpha emission. The radiative pressure combined with the winds from the hot star(s) floods the cloud and begins to dissipate the remaining material. The inhomogenous nature of the cloud is then made apparent as denser regions resist the winds and ionization, resulting in a multitude of cold dark "globules" and indentations near the edges of the glowing nebula. The great force of the stellar radiation is quite obvious as bright rims are formed along the edges of such dark features, typically the edges facing the direction of the hot stars responsible for all the action. Such "bright -rimmed clouds" are located throughout the Lagoon Nebula (Messier 8) near the bottom of this image. A closer look at the Lagoon and this phenomenon can be found by clicking here. When the dusty clouds are located near a bright star that is not energetic enough to ionize simple hydrogen, the microscopic dust grains of the cloud will often "reflect" the light of the nearby star(s). Such reflection nebulae are often blue in color due to the bluish colors of such bright stars and the size of the dust grains responsible for the reflection. The upper portion of the Trifid Nebula (Messier 20), located near the top of the above image, is a wonderful example of such an object. Other nearby objects of note include the small reflection nebula IC 4678 located along the lefthand side of M 8, a small red "ring"of nebulosity designated as GN17.58.8.1 is located to the right of the image's center, while the large tenuous HII regions NGC 6526 and Sharpless 2-26 reside on each side of the dark feature found directly between the Lagoon and Trfid Nebulae. Image taken with homemade 8-inch f/5.4 astrograph and SBIG STL-11000XM. LRGB image composed of 60 minutes each R,G,B and synthetic L channel. Click on the above image for the high resolution version.