Sh 2-312 is a nebula in the southern constellation of Pyxis. It is very large and diffuse, making it largely ignored and unstudied outside of its relation to the Gum Nebula. Sh 2-312 is located approximately 56 parsecs away from RCW 22, another nebula postulated to be a part of the larger Gum Nebula, which is itself estimated to be approximately 300 parsecs in width based on angular diameter approximation. It responds well to Hydrogen-alpha filters; however, it requires extended exposure time to become visible during observation.
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