It was initially catalogued by George Abell as a planetary nebula, but it soon became clear that it was an SNR. It was also recognized as a radio source and thus given the designation CTB 1.
LBN 576 is about 10000 light years away from us and is extremely faint. The Oxygen III content is very low, and lower than "usual" for this type of nebula.Imaging it (and further processing) has been a challenge for me, and I am not sure if I have been able to show all the information I collected.
On the right you can see first the Hydrogen alpha image which accumulates 21 hours of exposure.
The second image is a Ha - OIII - RGB composition which accumulates near 52 hours of exposure.
Click on the images for a 100% version or go to the Gallery section for complete exposure details.