I was looking into night vision equipment recently and found that some work with ultraviolet light. How much ultraviolet light is around at night? Is there enough ultraviolet light to see in the dark, without producing it? I don't care if it would be blurry, is it possible that there would be more ultraviolet light than visible light, even if it comes from artificial sources?
At night there is virtually no UV present. Most night vision devices work by amplifying low levels of ambient visible or near-IR light. Some (thermal vision devices) amplify long-wave IR emitted by normal temperature objects. In neither case is there enough UV to do any good.
Artificial lighting does not emit appreciable UV either - if it did it would pose a significant vision threat.