The Hades SNR sits on the border of Vela and Centaurus, close to the famous Carina Nebula. The surrounding area is full of quite bright H-alpha clouds, and the SNR bubble itself is partially hidden by the overwhelming light of these clouds. If we draw an imaginary bubble following the radius of the SNR’s curve, we get an approximate bubble diameter of around 4.5 degrees. We don’t know if the SNR actually continues around this circular path, but given the amount of deep narrowband imagery immediately around the Carina Nebula, it is not likely it forms a complete bubble because we would see it in other images.
