What the night sky looks like over Ottumwa, IA
Ottumwa reads as suburban edge on this dataset's scale. A noticeable glow near the horizon. Brighter stars and constellations are easy to pick out; the Milky Way is washed out. Only 27.2% of the 3,206 cities measured here read darker than Ottumwa.
The number comes from orbit, not a stargazer's logbook, so treat it as an estimate of sky glow rather than a certified Bortle class.
The nearest darker sky to Ottumwa
The closest place in this dataset with a meaningfully darker sky is Norwalk, IA, roughly 73 miles away in a straight line, rated rural. Road distance will be more.
Norwalk, IA is itself still a measured city, not a designated dark-sky park, this only compares against the 3,206 places this dataset covers.
Ottumwa against the rest of the dataset
About 25,648 people live in Ottumwa, IA, sized enough to appear in this dataset of 3,206 incorporated US cities. Among all 3,206 cities here, Ottumwa ranks 867 from darkest to brightest, 1 being the darkest measured.