The History of the Angell Hall Observatory

by Dave Snyder
Revised: November 2004

When the Student’s Observatory (see the Detroit Observatory) was torn down in 1923 to make room for a dormitory for nurses, the fifth floor of the Angell Hall (one of the University of Michigan classroom buildings) was reserved for a replacement observatory. With the exception of small amount of space used for other functions, the fifth floor has been used for that purpose to this day.

An chronology of events follows:

• 1926 - Two domes were erected on the roof of Angell Hall. A 10” refractor was installed in one and the other dome was reserved for future use.
• 1927 - The observatory was opened to student use. Visitor’s nights at Angell Hall were begun. These visitor’s nights continued until the 1980’s.
• 1928 - A 3” transit was placed in the observatorul
• 1929 - A 15” reflector (to be used by students) was installed in the unused dome.
• 1930 - A spectrohelioscope and sidereal clock were added to the equipment already at Angell Hall.
• 1993 - There was a plan to remove the two original domes and replace them with a single enclosed astronomical observatory. This was a small part of an approximately $12 million grant from the State of Michigan to the University of Michigan for the renovation of Angell Hall. Albert Kahn Associates (AKA) was selected as the architect for the renovation (they were also the original architects for the building). On September 10th and 16th, there was a meeting with AKA, H. Aller and P. Seitzer (Aller and Seitzer are both faculty members of the University’s Astronomy Department). Details of the restoration project are as follows:
  1. The decision to demolish the existing telescope domes and replace them with a single dome of modern design was made prior to AKA’s participation.
  2. Originally it was planned to locate the new observatory on the third floor roof on the south side of Angell Hall and on the fifth floor roof. There was careful consideration of several issues including: (a) an observatory on the roof would be subjected to vibrations from large air handler units located on the upper levels of the building, (b) student access and safety, (c) proximity to the Astronomy Department’s fifth floor labs and (d) cost. After considerations of these issues, a decision was made to locate the new observatory on the fifth floor.
  3. The new observatory would contain a 16” classical Cassegrain telescope manufactured by DFM.
  4. There would be a climate controlled, domed observatory large enough to hold a class. The dome would be built by Ash Manufacturing Company. This observatory would contain the following: (a) Ten pier mounted 8” Cassegrains with CCD link mounted on the roof, (b) CCD classroom connected to all scope locations, (c) an instrument room below the main observatory for an optics bench set up with provisions for a future solar telescope, (d) barrier free access to the observatory and the roof mounted scopes (the university has elected to construct the wheelchair lift and exterior ramps at a later date), (e) two astronomy classrooms with display area, and (f) an astronomy lab.
• 1994 - Both domes were dismantled, the telescopes removed and put into storage. The restoration project described above is started (with a few minor alterations). A new 18 foot dome was constructed above the fifth floor on the roof. A single 40 centimeter reflecting telescope (a Ritchey-Chretien with field corrector) was installed inside this dome. The telescope is totally computer controlled and has a CCD camera. On roof, but outside the dome, a set of piers have been placed. There are six Schmidt Cassegrain telescopes (all are 8”) which can be mounted on these piers. There are some additional CCD cameras which can be used with the 8” Schmidt Cassegrains.
• 1995 - This observatory is functional, it is used solely for instruction of students (primarily within introductory Astronomy courses). There are once again open houses at Angell Hall.

The 10 inch refractor originally at Angell Hall.

The 16 inch reflector originally at Angell Hall.

The 10 inch refractor after the optics had been removed. Note the construction rubble on the floor.

Photo Credits

The photograph at the beginning of this page shows Angell Hall and was taken October, 1999 by Dave Snyder. The observatory dome is visible on the roof. The other three photographs were taken by Chris Sarnecki before the telescopes were decommissioned in 1994.

Links

• The History of the University of Michigan Observatories.
• Bibliography.
• About Me
• Home

Modified August 11, 2025