Perched on Mount Pleasant in the town of Dryden, New York, the Hartung-Boothroyd Observatory (HBO) stands as a testament to the celestial curiosity that Cornell University has nurtured for decades. It is a gateway to the stars, a place where the heavens unfold in wondrous detail to the eyes of astrophiles and the lenses of powerful telescopes.
The observatory is home to a reflecting telescope, one of the largest in New York State dedicated to both education and research. This remarkable instrument, housed under a retractable dome, has provided students and researchers with direct experience in astronomical observations since its establishment in 1974.
HBO isn’t just an observatory; it is a bridge between the terrestrial and the cosmic. It represents an educational philosophy that values direct engagement with the subject of study. Undergraduates, graduates, and faculty members flock to the facility to engage in projects that range from studying variable stars and exoplanets to tracking asteroids. Here, theoretical astrophysics meets the tactile world, allowing for an integrated understanding of the universe’s complexities.
It is used mainly as a Cornell University (Ithaca, New York) teaching facility for upper-level astronomy classes. The observatory is named financial contributions of M. John Hartung ’08 (chemical industrialist and donor) and in honor of the labor of Samuel L. Boothroyd (founding professor and chairman of astronomy 1921–1942). The telescope construction began in the 1930s and the observatory was dedicated in 1974. It contains the James R. Houck 60 centimeter telescope and various instruments.
The James R. Houck telescope at HBO was a project initiated by its namesake in 1972, using optics and a lightweight tube which had been fabricated in the late 1930s by Samuel T. Boothroyd, Cornell’s first astronomer, and a mounting constructed by George Gull ’72 as his senior design thesis in Mechanical Engineering.
The telescope, control electronics and instruments are largely the result of work done by undergraduates since 1970. It was manufactured by the students at the Tompkins, Tioga and Seneca BOCES and by Therm, Inc., with mirror coatings by Evaporated Metal Films corporation, all in Ithaca. The latter corporation was founded by members of Boothroyd’s scientific team, as he pioneered the use of evaporated metal coatings in astronomical optics. The telescope and observatory were dedicated in 1974.
The primary mirror is made of Pyrex from the Corning Glass Works and is in fact from a 1/8-scale test pour by the Corning company in preparation for the making of the 200″ Palomar mirror. It is 0.635 m (25 inches) in size, but the outer half inch is masked. The focal length of the mirror is 2.5m (100″) or f/4.
The Cassegrain design of the James R. Houck telescope is a combination of a primary concave mirror and a secondary convex mirror, often used in optical telescopes, the main characteristic being that the optical path folds back onto itself, relative to the optical system’s primary mirror entrance aperture. This design puts the focal point at a convenient location behind the primary mirror and the convex secondary adds a telephoto effect creating a much longer focal length in a mechanically short system.
The secondary is an 8″ mirror made of Cervit (a low thermal coefficient material). In combination with the primary, it yields a final f/13.5 beam to the nominal focus, which lies 18.5″ behind the primary mirror’s vertex. At nominal focus, the plate scale is about 24 arcsec/mm, with an effective focal length of 8.57 m.
The telescope, control electronics and instruments are largely the result of work done by undergraduates since 1970. It was manufactured by the students at the Tompkins, Tioga and Seneca BOCES and by Therm, Inc., with mirror coatings by Evaporated Metal Films corporation, all in Ithaca. The latter corporation was founded by members of Boothroyd’s scientific team, as he pioneered the use of evaporated metal coatings in astronomical optics.
The dome itself, like all professional observatories, is unheated. The telescope and instrumentation can be controlled from a neighboring control room which is heated and offers standard amenities plus several computers for simultaneous data reduction.
The observatory was founded by James Houck and managed by him through 2006. The principal contact is Don Barry, who managed the facility from 2006-2015, and taught Experimental Astronomy using the facility.
“Graduates” of the HBO project are now senior engineers and technical managers as well as graduate students, research associates and faculty at major universities.
Moreover, the observatory is a beacon for interdisciplinary collaboration. It’s not uncommon to find astronomers working alongside computer scientists, engineers, and educators. This cross-pollination of ideas enhances the potential for innovation, fostering new techniques in data analysis, instrument design, and educational methods. The observatory’s role extends beyond its primary function; it is a hub of convergence for diverse academic disciplines, all under the umbrella of exploring the unknown.
HBO also contributes to the global astronomical community through its research. The data collected here feed into larger networks of observation and analysis, aiding in the collective endeavor of mapping and understanding the universe. Its strategic location in upstate New York, away from the light pollution of large urban centers, grants it relatively clear night skies, making it an invaluable resource for both optical astronomy and astrophotography.
In an era where space exploration has captured the public imagination like never before, observatories such as the Hartung-Boothroyd are more crucial than ever. They serve as terrestrial launchpads, propelling minds into the realm of scientific inquiry. Here, the vastness of space becomes approachable, the mechanics of the cosmos decipherable, and the mysteries of the universe a little less mysterious.
As the night falls and the stars emerge, the Hartung-Boothroyd Observatory continues its silent vigil over the heavens. It stands as a beacon of knowledge and discovery, an educational catalyst, and a gateway to the stars. For the students and astronomers who work from this dome on Mount Pleasant, HBO is more than an observatory—it is a vessel navigating the infinite ocean of the night sky, a journey that begins in the heart of Cornell University and extends to the edges of the observable universe.
Michael Stephen Wills Photography 