The map shows the whole sky, with the galactic center in the middle.
Okay, dumb question - what galaxy? 'The Whole Sky' is more than our galaxy, the Milky Way. I read and searched the entire article and it doesn't clarify???
Or am I missing something? (wouldn't be the 1st time, nor last)
Not a dumb question. It’s a map in the gamma ray part of the EM spectrum. So visible light isn’t shown. The whole sky is represented as a globe (notice it goes from 90-degrees North to -90-degrees South, and 360-degrees latitudinally). What it shows is the shape and extent, or size, of the region of gamma ray emissions in our galaxy relative to the entire sky, with the Milky Way centered. There are other gamma-ray sources out there, of course. Don’t know why they chose not to represent at least a few of them on the map.