U.S. News Insider Tip: Try to plan your evening at the Lowell Observatory around the weather, as clear skies (read: no cloud cover) make all the difference. The observatory recommends checking the ...

Lowell Observatory began exploring the stars, almost 20 years before Arizona became a state. Now it's being crowned one of the best in the entire United States.

Lowell Observatory's founder, Percival Lowell, is credited with the research that led to the discovery of Pluto in 1930. Lowell also studied the planets Mars and Uranus.