The Cat’s Butt Nebula – NGC 2467 & Sh2-311

More commonly known as the Skull & Crossbones Nebula, I prefer the name my wife gave it: The Cat’s Butt. Located roughly 4,420 light years away in the Puppis constellation, it’s a very busy star-forming region. Some disagreement exists on the distance of NGC 2467 and its various components with some estimates ranging as far as 21,000 light years.

NGC 2467 has been useful to scientists in determining how already existing large, hot stars affect stellar formation in these gaseous regions. A Spitzer Space Telescope study found 45 protostars (newly forming stars) all positioned along the edge of the gas cloud along the edge of an ionization front created by nearby massive, hot stars. This leads scientists to conclude that the gas compression along the front triggers star formation, and thus the aforementioned large stars have a significant affect on the births of their brethren.

The light blue circular formation above and right of center is a compact star cluster, catalogued as Haffner 19, containing what is called a Stromgren sphere. A Stromgren sphere is a cloud of gas surrounding a hot, ionizing star. The cloud usually has a distinct boundary and typically appears in roughly circular form.

Note that this image uses a combination of data taken using the Celestron EdgeHD in 2021-22 and the Planewave CDK12.5 in 2025.