Theodor Jacobsen Observatory

The Theodor Jacobsen Observatory is an astronomical observatory located on the University of Washington campus in Seattle. It houses a six-inch Brashear lens telescope mounted on a Warner and Swasey equatorial frame, all contained within a rotating metal dome.

The observatory was built in 1895 using sandstone from nearby Denny Hall, making it the second-oldest building on the University of Washington campus. The telescope mounting system was later integrated with historical materials that serve a practical purpose in the instrument's design.

The observatory welcomes visitors for regular viewing sessions where people can look through the telescope and learn about the night sky. These events bring academic science and the community together, making astronomy accessible to anyone who wants to watch the stars.

Visitors should check the official website beforehand to register for a viewing session, since the observatory operates on a fixed schedule. Booking in advance ensures you can join one of the public observation nights without disappointment.

The telescope mount rotates on cannonballs from the Civil War era, an unusual way to use military relics in a scientific instrument. This practical approach shows how early astronomers creatively solved engineering problems with materials at hand.

Location: Seattle

Website: http://astro.washington.edu/observatory

GPS coordinates: 47.66040,-122.30900

Latest update: December 12, 2025 17:44