Mount Cuba Astronomical Observatory is an astronomical observatory is located at 1610 Hillside Mill Road, Greenville, Delaware, United States. This observatory is home to a 0.6-meter telescope used by the Delaware Astronomical Society, the University of Delaware, and the Whole Earth Telescope. The DAS is composed of interested amateurs and engages in astronomy education and public outreach. Meetings are held the third Tuesday of each month at the Mt. Cuba Astronomical Observatory.
A Sunquest sundial, designed and machined by Richard L. Schmoyer, is on the Mount Cuba Observatory grounds near the parking lot. This mean time sundial automatically corrects for the equation of time through the use of an analemma-inspired gnomon.