Located on top of Carleton's Herzberg building, the Kessler Observatory is named after Dr. Dan Kessler, a long-time faculty member who who was instrumental in the establishment of the observatory in the 1980s. In 2011, the observatory was modernized, and it now houses three telescopes; a 14" Schmidt-Cassegrain, a 4" apochromatic refractor, and a 60mm Hα solar telescope.

The observatory is primarily used for instructional purposes as a part of several astronomy courses offered by the Physics Department.  It is also occasionally open to the public, during the Department's Astronomy Nights.