Facilities
Sawyer 24-in Reflector
The 24-in reflector at Whitin Observatory,
built by Boller and Chivens in 1966,
was a gift from Mrs. Margaret Sawyer.
Its f/13.5 Ritchey-Chrétien Cassegrain optics are
presently used with an additional focal length reduction lens
yielding an effective focal ratio of f/9.6.
In 1991, the original telescope drives and relay control system were replaced with a computerized retrofit motion control system by DFM Engineering. Several subsequent improvements were made to the telescope during the summer of 1995, including a DFM upgrade to the control system, installation of a DFM “Guide-Acquire Module” with broadband photometric filters from Omega Optical, and changes to the dome and structure to improve the seeing. In 2003 December the control system software was upgraded to a Windows-based version, once again by DFM.
The original instrumentation accompanying the telescope was a Boller and Chivens 4 × 5-in photographic plate camera. Other instruments that have been used on the telescope in the past include a photoelectric photometer (ca. 1969), an Optomechanics Research Model 10C Grating Spectrograph (ca. 1982), and a Photometrics 512×512 CCD camera for electronic imaging (1990). The imaging CCD instrument presently on the telescope is a Photometrics/SITe 1024×1024, 16-bit, back-illuminated, Metachrome-coated CCD camera which has been in use since 1995.
The 24-in telescope and its instrumentation has been used since it was installed in 1966 to teach observational astronomy techniques to intermediate and advanced students. It's also heavily used to carry out research programs at the Whitin Observatory. At present the main research observing program is an ongoing study of the spin properties of Koronis family asteroids. Past projects include long-term observations of symbiotic binary star systems, variable star and supernova monitoring, and study of extrasolar planets by detecting transits in front of the orbited stars.
(next page: Fitz/Clark 12-in refractor)
