Lisle, IL Night Sky Brightness
Lisle, IL's night sky, measured from orbit
Satellite radiance puts Lisle in the suburban band. Light dome dominates much of the sky. Only the brightest stars and planets stand out clearly. Only 58.5% of the 3,206 cities measured here read darker than Lisle.
Note the source: a satellite reading of upward light, not a visual Bortle scale reading. The two measure related but different things, explained in the Bortle scale guide.
How far Lisle is from a meaningfully darker sky
Downers Grove, IL, about 3 miles away as the crow flies, measures in the suburban edge band, one step darker than Lisle. Actual driving distance will run longer than that straight-line figure.
Downers Grove, IL is itself still a measured city, not a designated dark-sky park, this only compares against the 3,206 places this dataset covers.
How Lisle compares nationally
Lisle, IL counts roughly 23,548 residents, among the 3,206 US cities this site tracks. Lisle's position, 1,867 of 3,206, darkest to brightest, comes from the sampling method the methodology guide sets out.