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Written in the Stars

Plans for a new Detroit Observatory renovation bring the campus’s second-oldest building into the 21st century.

by Robert Havey

The Detroit Observatory, the oldest academic building on campus, is being renovated for the 21st century. On March 26, 2019, the U-M Board of Regents approved a plan that will add 7,000 square feet of additional program and support space, while preserving the historic Observatory itself.

The Detroit Observatory was built in 1854 as part of U-M President Henry Tappan’s plan to transform the University of Michigan into a world-class research facility. Tappan commissioned the Fitz Refracting Telescope, which was one of the largest in the world when it was installed in 1857. (The telescope was fully restored in 1999 and will be available during public viewings after the construction is completed.)

The Observatory immediately contributed to the academic prestige of the University. Measurements were made at the Observatory that were used to calibrate precise timepieces for local banks and rail stations, making Ann Arbor run on “Detroit Observatory Time.” U-M faculty members discovered and named more than a dozen asteroids.

The expansion of the University and the city made the Detroit Observatory’s location less and less ideal for serious academic work. The building fell into disuse after the Astronomy Department moved to the Dennison Building (now Weiser Hall) in 1963. In 1994, U-M President James Duderstadt and his wife, Anne, led an effort to restore the Observatory to its original 1854 condition. The Bentley Historical Library took over Observatory operations in 2005.

Construction is slated to start in May 2019 and is scheduled to be completed in 2021.