What 1° x 1° region of the night sky has the lowest flux of light?

(considering the typical visual/luminance filter range, approximations using other filters/bands are acceptable, but should be in the optical)

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    $\begingroup$ This is a cool question! I have a hunch there's an answer out there somewhere. One candidate might be the surrounding neighborhood of something like the Hubble Ultra Deep Field (itself only 3 x 3 arcminutes) away from the milky way or other diffuse sources and any particularly bright stars which could induce scattered light artifacts in the telescope. $\endgroup$
    – uhoh
    Oct 2, 2022 at 1:57
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    $\begingroup$ I agree with @uhoh-- this would be a cool project, but I'm not sure if anyone has made the calculation so far. I'm guessing it would be in the general direction of Fomalhaut (but obviously not including Fomalhaut) since that's the shortest way to leave the galaxy from earth. You could use something like GAIA3 to make the computation, though other sources may work as well. $\endgroup$ Oct 2, 2022 at 10:12
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    $\begingroup$ @BarryCarter I'm currently attempting this with the Gaia (DR1) catalog, however there are a few limitations: the catalog does not include bright stars, and the darkest total flux regions are often caused by nebulas, where the total flux may be different. Filtering this doesn't seem to be easy $\endgroup$
    – 2080
    Oct 2, 2022 at 13:12
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    $\begingroup$ github.com/barrycarter/bcapps/blob/master/WORDPRESS/… was on my now-deleted blog once. $\endgroup$ Oct 6, 2022 at 2:35
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    $\begingroup$ github.com/barrycarter/lowestflux/tree/main/barry pretty much answers the question using SQL-like queries on the GAIA site itself. I've requested a pull back to the main repo $\endgroup$ Nov 20, 2022 at 15:05


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