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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)

2080
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    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. – uhoh Oct 02 '22 at 01:57
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    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. – Barry Carter Oct 02 '22 at 10:12
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    @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 – 2080 Oct 02 '22 at 13:12
  • The HYGData set is a lot smaller and easier to filter, but has far fewer stars. Of course, the (extended) Pareto principle might work here: the n brightest stars may provide 99%+ of the brightness for a given grid square. Occupy the Milky Way... sorry :) – Barry Carter Oct 03 '22 at 09:39
  • @BarryCarter Whether that holds is a pretty interesting question itself! – 2080 Oct 04 '22 at 11:45
  • Are you doing this on github? I'm paralleling your effort (not yet on github) using HYG – Barry Carter Oct 04 '22 at 12:39
  • @BarryCarter I have put the code here: https://github.com/void4/lowestflux – 2080 Oct 05 '22 at 01:13
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    https://github.com/barrycarter/bcapps/blob/master/WORDPRESS/wordpress.barrycarter.info/occupy-the-milky-way.wp was on my now-deleted blog once. – Barry Carter Oct 06 '22 at 02:35
  • @2080 Wow, you finished it? – Barry Carter Oct 06 '22 at 12:48
  • @BarryCarter For now I've only checked out regions, not the entire sky. Will return to do that later – 2080 Oct 07 '22 at 17:01
  • I rather fancy it will be a square degree in the Taurus molecular cloud - but I'm not really clear what figure of merit you are trying to minimise. Total V-band fliux? I don;t think you can answer this by just summing up bright stars. The log N vs log flux relation is steeper than 1 down to 16th mag or so. But I think looking towards a nearby dark cloud eliminates that problem. – ProfRob Oct 16 '22 at 14:56
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    https://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 – Barry Carter Nov 20 '22 at 15:05

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