A Brief History of the Observatory

On the night of October 27, 1965, a new 16-inch telescope situated in a new observatory on the CSU campus drew its very first light from its first observed object, the planet Saturn. The observatory had long been a dream of M. Leslie “Les” Madison, who taught at CSU from 1935 to 1972 and served as the Chairman of the Mathematics Department from 1956 to 1968.

At the start of the twentieth century, astronomy at CSU was initially taught out of the Mathematics Department by Stuart Lincoln Macdonald. To aid in his teaching of astronomy, in 1905 Macdonald obtained an extremely high quality 4-inch Alvan Clark refractor which served as the primary astronomical instrument at CSU for over 60 years and has the distinction of being the oldest recorded item currently on CSU’s equipment inventory. This refractor was eminently portable and occupied various locations around and near the CSU campus as a sort of “roving observatory” all the way into the 1960s.

After serving in the South Pacific in World War II and after Macdonald’s retirement, Les Madison took over the responsibilities of teaching the astronomy class at CSU. He was fond of telling his class right before the final that if they passed his astronomy course, they would have more college credits in astronomy than did he! In 1965, he was the principal driving force behind the construction of a permanent on-campus sliding rooftop observatory equipped with a 16-inch Cassegrain reflector built by the Cave Optical Company, then one of the premier telescope manufacturing companies in the world. At the time of its completion the CSU reflector was the third largest telescope in Colorado, behind only the Summers-Bausch 24-inch reflector at CU and the magnificent 20-inch Alvan Clark refractor at DU’s Chamberlin Observatory. CSU’s Clark refractor was soon mounted alongside of the new reflector, thus generating a most impressive “two-shooter” telescope array.

When the CSU Observatory was built in 1965, its present location, just off the university intersection of Pitkin Street and East Drive, was an excellent dark sky site and the astronomical data obtained with this telescope array contributed to several journal publications in the late 1960s.

Since then, the sky-glow from both campus and city lights have precluded any research uses for these telescopes, but they nonetheless continue to serve both astronomy students as well as the general public. Weather permitting, the observatory is open for public observing every first and third Friday from April through November.

On May 16, 1986, a dedication ceremony was held at the observatory on the CSU campus in which the CSU Observatory was formally named the Madison-Macdonald Observatory in honor of the two academics who taught astronomy at CSU for a combined total of more than 60 years. Each time the roof of the Madison-Macdonald Observatory slides open on a clear night and the plaques and telescopes of Les and Stuart become bathed in starlight and Moon glow, one can’t help but feel in the presence of such a sight that these remarkable men must certainly now be a part of the firmament that they loved so very much.

Adapted from: Culver, R. (2015). CSU observatory lives on past its pioneers. Coloradoan.