The Goethe Link Observatory is located on a high bluff about 3 miles south of Mooresville, Indiana on US 67 Indiana. The large 36" telescope was built as the private observatory of Dr. Goethe Link, a noted Indianapolis surgeon and amateur astronomer.

Construction of the Observatory started early in 1937 and was operational in early 1939. It contains a 36-inch folded Cassegrain reflector. The primary mirror was a test blank that had been poured as experimental in development for the 200 inch mirror for the Mt. Palomar Telescope. The visual tests showed the surface of the glass was ranked as one of the most accurately figured mirrors ever made at that time. The original telescope was a Newtonian, but in 1966 an entirely new telescope tube with f/10 Cassegrain optics was installed. The original f/5 primary mirror was retained, but its ribbed construction prevented cutting the central hole needed for a normal Cassegrain focus. Instead, a tertiary flat was inserted to reflect the converging beam of light from the secondary and direct it toward any of three observing ports at the circumference of the tube. The telescope alone weighs 5,000 pounds.

The concrete pier extends down to solid bed rock, weighs 200 tons and extends 30 feet above ground level. The dome is 34 feet in diameter with an opening 8 feet wide and weighs 34 tons. The opening extends 4 feet past the zenith, and the shutters weigh one ton each. The building was hand constructed of oak posts and knotty-pine paneling and does not touch the pier thus keeping any vibrations from transferring to the pier and the telescope. On the first floor there is an auditorium, a darkroom, living quarters, and a library. Just below the observing deck there is a 250-square foot control room with inclined glass windows that look into the dome and observation deck.

Donated to Indiana University School of Astronomy
The Goethe Link Observatory was donated to Indiana University in 1948 and was used regularly for astronomical research until the mid-1980's, by which time the night sky brightness from the Indianapolis suburbs had substantially restricted the breadth of research possible from the site. Instruments used there during the 1950-80's include a photographic camera, photoelectric photometer, scanning spectrometer, and slit spectrograph. Topics studied include galactic clusters, cool star spectrophotometry, and spectroscopy of interacting binary stars.

Achievements in Scientific Research - Indiana Asteroid Program
The observatory complex was used during the 1950-60's to recover asteroids whose orbits had been "lost" during the interruption of regular astronomical observations that occurred worldwide during World War II. The Indiana Asteroid Program was initiated by Frank K. Edmondson of Indiana University in 1949 and continued until 1967. By 1958, the program had produced 3,500 photographic plates showing 12,000 asteroid images and had published about 2,000 accurate positions in the Minor Planet Circular. When the program ended, it had discovered a total of 119 asteroids and many new minor planets, and was a leading program for asteroid discovery world-wide. The program's nearly 7,000 photographic plates are now archived at Lowell Observatory.

The Observatory Today
The observatory is now operated jointly by Indiana University School of Astronomy, the Link Observatory Space Science Institute and the Indiana Astronomical Society, an amateur astronomy group based in central Indiana to which Dr. Link belonged.

Link Observatory Space Science Institute
Today, this magnificent astronomical observatory is dedicated to providing informal, yet expertly designed, science education to schools and the general public throughout central Indiana. Its mission is to inspire students to pursue studies in science, technology, engineering and math (STEM) and encourage students in all disciplines to explore and achieve their greatest potential.

Photos Courtesy Forrest Mellott