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Rosemary Hill Observatory

Located 30 miles from the University of Florida campus, in an isolated hilly region, Rosemary Hill is the University’s optical research observatory. Founded in 1967, it was funded by an NSF Center of Excellence grant. The 80-acre site was donated by a public-spirited citizen, Mrs. Marie Hergert. The facilities include two telescope domes, a dormitory, and utility buildings. Through the generous cooperation of Mr. Bob Cremer, then Director of the University’s Physical Plant, the infrastructure was completely renovated in 1993-4, and the interior roads were paved in 1995. Satellite photos show Rosemary Hill near the center of the largest dark area in north Florida; stars as faint as 22nd magnitude have been recorded on slow, fine-grain plates.


The Rosemary Hill Observatory is a private observatory located close to Bronson, in Florida, 30 miles away from Gainesville.

30-inch Reflector

The principal instrument is a 30-inch (76-cm) Tinsley reflecting telescope that can be used at the f/4 Newtonian focus or the f/16 Cassegrain focus. Pointing is indicated by digital readouts. The instrument is equipped with a Photometrics CCD camera, filter wheels, and standard photometric filters. An autoguiding system has recently been added. The dome carries flat-fielding targets, and a motorized ladder facilitates work at the Newtonian focus. The CCD camera can be mounted “piggy-back” on the 30-inch and used with Nikon camera lenses for wide-field work. Auxiliary equipment includes an Astromechanics photoelectric photometer and a Boller and Chivens spectrograph.

Regular monitoring of the brightness fluctuations of active galactic nuclei has been carried on by Professors Alex Smith and Robert Leacock since the commissioning of the telescope in 1968. In recent years much of this work has been done in collaboration with spacecraft such as the International Ultraviolet Explorer and the Compton Gamma Ray Observatory. Shorter-term programs have included photometry of eclipsing binaries by Professors Wood, Chen, Oliver, and Cohen; sky-limited photography of galaxies by Professor Gottesman; monitoring of lunar occultations by Professors Oliver and Cohen; spectrographic studies of stars by Professor Oliver; and measuring light curves of asteroids by Professor Telesco. Lately it has also been used to do photometry of a transiting extrasolar planet. The instrument has also been used extensively in teaching laboratories at the graduate and advanced undergraduate levels. Sixteen graduate students have earned their doctorates through research conducted on the Tinsley reflector.

18-inch Ritchey Chretien

After a period of disuse this smaller, user-friendly telescope was restored to full operation in 1994 through the efforts of Professor Oliver and graduate student Scott Fisher. Digital control of pointing is obtained from encoders on the axes, which are driven by stepping motors, and digital readout of focus has been installed. The generosity of Professor Telesco made possible the purchase of an SBIG ST-8 CCD camera for the 18-inch, so that autoguiding is now available, while a computer-controlled filter wheel adds the capability for three-color photography. The refurbished instrument is ideal for instructional use in laboratories at the graduate and advanced undergraduate levels, and is seeing extensive use for this purpose. With the help of contributions from various donors, the 18-inch has been computer controlled and automated for remote operation.

Visitor Use

Rosemary Hill has always welcomed use by visiting astronomers. Visitors in recent years have included Diethelm from Switzerland, Piner from the University of Maryland, Clements from Western Kentucky University, and Nair and Jang from Georgia State University. The visitors have generally resided in the dormitory, often for periods of a month or more. Jang recently completed a Ph.D. dissertation based largely on 241 nights of observations at Rosemary Hill. The Observatory is opened occasionally for visiting classes or local organizations.