Photos are often copied about the web with modifications, but I think this one actually does probably refer to a non-modified version of the original. The original picture does have an artificial quality about it. It's possible the critic is talking about a different picture, but probably he's mistaken. If it were me, I would just send him an email to ask. (I might even copy D. Green, the study lead.)
In a sense all such "photos" are faked, because they are all manipulated to some extent. Let's look at the credits.
Supernova remnant G1.9+0.3. Image Credit: X-ray (NASA/CXC/NCSU/S. Reynolds et al.); Radio (NSF/NRAO/VLA/Cambridge/D. Green et al.); Infrared (2MASS/UMass/IPAC-Caltech/NASA/NSF/CfA/E. Bressert)
This is clearly a composite image from 3 sources: X-ray, radio, and infrared. (Nothing wrong with that, btw.) Also, any of these sources aren't like photographic images - or, they are like photographic images where the colors have been shifted around ... because, people can't actually SEE x-ray, radio, or infrared. Again, nothing wrong with that.
I don't do a lot of work with images, but I can imagine there's a bit of artistic license in putting things like this together. How could there not be?
The "blue ball" is not really a ball. It could be the front of some wave or it could be just a bit of haze that accidentally resembles a sphere to our human brains. It's translucent and you can see something (stars? flecks of gas?) through the other side and it's concentrated near the upper part of the image. Our brain just fills in the "sphere."
I wrote all this before hand, but now I clicked the image and find it here, confirming some of what I had inferred:
http://chandra.harvard.edu/photo/2008/g19/The critic was right that real objects in the sky don't look like this. There are probably a lot of crazy things percolating about this image - that it's a planet or star in our solar system or some other silly crap.
