A very deep shot of NGC 5792 in Libra. The catalogue positions of some 22 quasars and active galactic nuclei, together with their spectral shift z are shown, using NASA's million quasar catalogue.
https://heasarc.gsfc.nasa.gov/W3Browse/all/milliquas.html
The catalogue is patchy, and by luck only covers the bottom half of the image.
Two of the objects circled are relatively close (z around 0.1), and show a resolvable galaxy. Most are at extreme distance, over 8 billion light years. They are intensely blue. The light would have been ultraviolet when emitted. The furthest has a z of 3.5, the light having been emitted about 12 billion years ago.
Aspen CG16M on 20" PlaneWave. Lum 18rhs, RGB 3hrs each, all in 1hr subs.
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