The report stated "The object in question is a rare, ring-shaped galaxy measuring some 100,000 light-years across (slightly larger than the
Milky Way) and located 600 million light-years from Earth. In a recent image of the oddball object taken by the Hubble Space Telescope and processed by geophysicist
Benoit Blanco, a bright ring of billions of blue stars forms a perfect circle around a much smaller and denser sphere of reddish stars. In the dark gap between the two stellar circles, another ring galaxy — much, much farther away from us — peeks out to say hello."
Good information but I like the z numbers for both objects shown. A ring of blue stars circling a denser area of red stars is a problem using H-R star diagram dating, thus the implied great age differences between the stars shown in the ring and denser sphere of red stars. Galaxy z numbers for redshifts can be compared using the flat universe model for inflation (the common and accepted model used) and the open universe model. You get different distances and age results.