View this project online here: https://mybinder.org/v2/gh/nbartzokas/rosat-allsky/master?filepath=ROSAT.ipynb
In this python notebook, we will reproduce the image above. It's a colorized composite of data from the ROSAT All-Sky Survey available from NASA here: https://heasarc.gsfc.nasa.gov/docs/rosat/gallery/misc_allsky1.html. The ROSAT was launched 30 years ago on the day of this writing. Its observations were completed in 1990-1991 and were composited at a low resolution. The high resolution TIF format version is only 1633x815 pixels.
The image we're trying to replicate was published in M.J.Freyberg, R.Egger (1999), "ROSAT PSPC All-Sky Survey maps completed", in Proceedings of the Symposium "Highlights in X-ray Astronomy in honour of Joachim Trümper's 65th birthday", eds. B.Aschenbach & M.J.Freyberg, MPE Report 272, p.278-281, Fig.4.