The Rosette Nebula

For your edification, the Rosette Nebula (ngc2237-39-44, amongst others), a large globular shaped ball of HII (singularly ionised Hydrogen gas) and dust lying approx' 5000ly away, in the constellation of Monoceros (the Unicorn). Weighing in at some 10000 solar masses and around 130ly across, the Rosette dwarfs its more famous neighbour, M42. The group of stars that form the central cluster of the nebula heat the gas in the nebula up to around 1-10million K, creating the conditions for the production of soft X-rays which have been detected in the nebula. Many of the stars in the central cluster are large B class stars with surface temps over 20000K. These stars also create the central cavity that you see in the nebula, which in fact is a bubble-spherical region cleared out by the intense radiation pressure generated by these stars. Part of the giant Monoceros Molecular Cloud Complex, the nebula sits on the outer edge of the region, where shockwaves from massive stars and nearby supernovae have compressed the gas to form new stars and bright nebulae, such as the Rosette.

Pic was take with t68 (iTelescope, NMSO), 12x60sec subs.
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