Within the Rosette
This close-up of the Rosette Nebula (NGC 2237) does a great job of showing off the star cluster (NGC 2244) that was formed just a few million years ago from the gas and dust in this stellar nursery. Those energetic young stars are clearing the area at the center of the nebula with their strong stellar winds and radiation. The central cavity measures about 50 light-years across, and the Rosette nebula itself is about 130 light-years across. In addition to sculpting the interior of the nebula, the young star cluster is also responsible for illuminating this emission nebula, with the strong ultraviolet light of the stars ionizing the surrounding gas, setting it aglow.
Located about 5,000 light-years away in the constellation Monoceros, the Rosette can be seen with binoculars or a small telescope. The image seen here, sent in by one of our readers, brings out details with long exposure and selective filtering. Stefan used two hours of HA (hydrogen-alpha) exposure and another two hours of OIII (Oxygen) exposure to provide the higher contrast needed to image the diffuse Rosette. We really like the way it shows how the cluster is shaping the surrounding nebula and the details it brings out in the knots of dust and gas.
Image credit: Stefan Muckenhuber (x)