How bright can such a QSO searchlight appear in the sky?
More Active Galaxies and Quasars
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Here on Earth, no QSO or AGN is visible to the unaided eye. The brightest QSO as seen from Earth is 3C 273. It is about two billion light-years from Earth, which makes it a challenge for most small amateur telescopes to find. Compared to other distant objects, however, QSOs are brilliantly bright and relatively easy to detect with large astronomical telescopes. Several quasars known to be more than eleven billion light-years from Earth are more easily visible than the Sun would be if it were only one thousand light-years away.