Plano, IL Night Sky Brightness
How dark is the sky in Plano, IL?
Plano's sky measures dark sky here. Among the darkest skies of any US city in this dataset. The Milky Way should be visible overhead on clear, moonless nights. That's brighter than 1.7% of the 3,206 US cities in this dataset.
Worth remembering: this is satellite radiance, not a ground observation. A true Bortle rating needs a human eye at night, this is the closest large-scale substitute, covered fully in the Bortle scale guide.
Plano is already about as dark as this dataset gets
Nothing in this dataset's 3,206 US cities measures a darker sky than Plano. That doesn't mean nowhere is darker, unincorporated land and wilderness aren't part of this dataset at all, only incorporated cities of 10,000 people or more.
Plano against the rest of the dataset
About 12,677 people live in Plano, IL, sized enough to appear in this dataset of 3,206 incorporated US cities. Ranked against the other 3,206 cities here by the methodology guide's own sampling, Plano comes in at 56, darkest to brightest.