YozoraAtlas

How dark is the sky in District of Columbia?

Sky darkness for Washington (17.12, Bortle 8), so far the only place in District of Columbia on Yozora Atlas, worked out from NASA satellite images of light at night (2025).

19 Bortle class, 1 pristine to 9 city center park or dark-sky place city

Numbers like 21.95 or 16.97 are the brightness of the sky overhead on a clear, moonless night, in mag/arcsec². The scale runs backwards: a lower number means a brighter sky, from about 22 for a natural sky to about 17 in a city center.
How the readings are made

NASA satellite night-lights map of District of Columbia with every place marked

Darkest skies in District of Columbia

  1. WashingtonBortle 817.12

Among the places on this site. Plenty of land between them is just as dark, with no town or park to name it by.

All 1 place in District of Columbia

Amber names are parks and certified dark-sky places. The figure is the Bortle class: 1 darkest, 9 city center.
Washington8