Marshall W. Alworth Planetarium

University of Minnesota Duluth, 1049 University Drive
Duluth, MN 55812



The Darling Observatory
John Darling was born in Michigan on April 15, 1847. He earned a degree in civil engineering from the University of Michigan and worked for the government for much of his life. After retirement, Darling moved to Duluth in 1913, where he enjoyed years of stargazing. Mr. Darling observed the night sky from his backyard, often inviting his neighbors over to observe with him. When his neighbors showed interest, he was inspired to give public addresses illuminated by lantern light.

After years of increasing public interest, Darling decided in 1915 to construct an observatory in Duluth. He received permission to use the land on West 3rd St. between 9th and 10th Avenues to build his observatory, (modern day Observation Park) provided he open it to the public, which, according to his memoirs "was entirely agreeable to me, as it was already my intention to share with others the pleasures and benefits which the larger telescope might afford."

The larger telescope that he wrote of is the nine-inch refracting telescope that now sits in the planetarium lobby. Originally, he ordered an eight-inch lens from Gaertner & Co of Chicago; however, they could not acquire the glass required due to the demands of the First World War. Soon thereafter, John A. Brashear Co of Pittsburgh came forward with a nine-inch lens they had made, and Darling was happy to buy a larger lens.

Construction on the observatory began in 1917, taking ten months to complete. The weather on the day of the observatory’s completion was cloudy, but the next night, April 17, 1917, (Darling's 70th birthday), Darling pointed the telescope to the stars for the first time. The first object he observed was the planet Saturn and its rings. The event was later featured in Popular Astronomy's October 1917 issue.

Darling opened the observatory to the public six evenings every month to groups of about 15 people. Before each viewing, Darling gave a lanternslide presentation in the waiting room before allowing visitors to look through the telescope. By 1920, over 3,000 visitors had come to the observatory!

In 1925, Frank A. Halstead joined Darling in operating the observatory. Halstead firmly believed in UFO's, and frequently gave presentations about them. When Darling died in 1942, the observatory was given to the city of Duluth, and Halstead took over as curator.

Several years later, the observatory closed its doors permanently due to a lack of interest and vandalism of the dome. The dome ended up in the junkyard (the current location of Canal Park), and the telescope was taken apart and laid to rest in the tunnel beneath UMD. Many years later, Eric Norland suggested to Don Jackson that the telescope be put on display in the planetarium lobby, which at the time was completely open and empty. Jackson liked the idea, and after pulling some strings, the telescope found a good home on permanent display in the planetarium lobby.

The Planetarium:
The Planetarium was built between 1965-1967 with a generous donation from Mr. Marshall William Alworth (1882-1980) costing nearly $200,000. When it first opened, Don Jackson served as director. In 1967, Jackson began work to acquire a black Brashear telescope from John Novak, a watch shop owner from Escanaba, Michigan. After testing the telescope with the planetarium staff, he convinced UMD to buy the telescope for $950.

In 1970, a 16-foot observatory dome was placed above the physics. Inside of it was installed a 16 inch Cassegrain telescope built by Group 128. The telescope was remotely controlled by a hand paddle and had a rapid focuser, or fine focus knob combined together. It and the dome were removed from service in 1985, due to poor performance. Marshall W. Alworth Planetarium

In 1975, the planetarium was renamed after its primary benefactor, Marshall W. Alworth. At about that same time, Eric Norland, a U.M.D. art major (and current Arrowhead Astronomical Society President) first painted and installed astronomically themed black light panels on the planetarium walls. Later in 1986, Jerry Beilike retouched and copied them directly onto the concrete walls as they appear today. In 1979, Don Jackson retired from his position as planetarium director and Glenn Langhorst, an amateur astronomer and science graduate, succeeded him as director.

In the late 1980's, the planetarium was in dire need of renovations, as seats had begun to break while visitors were sitting in them! Glenn Langhorst persuaded the university to install new seats and carpeting and in 1990, a new roof was put on the planetarium. After the renovations were completed, the University completely rescinded funding for the planetarium. For years thereafter, the Planetarium was without a director, funding or a clear direction.

The Present Day:
In 2006, the University appointed Dr. Howard Mooers as director, a position that he holds to this day. In the summer of 2011, Dr. Mooers convinced the University to fund a massive overhaul of nearly the entire planetarium. The seats, carpet, lighting, sound equipment and old control panel were all removed and replaced with all new, modern ones. Additionally, the dome was cleaned; a gift shop and museum were added as well as an all-new Full Dome projection system.

Thanks to the expanded capabilities of the planetarium, we now are able to present the wonders of the cosmos to the public like never before. We provide 2 free public shows a week and now offer our “Stellar Saturday” using our new Full Dome projection shows twice a day for a very small charge.

The Future:
Thanks to the continual donations and support of the public, we will continue in the tradition of the John Darling in educating the public on the ever-exciting developments in Astronomy.

Currently, we are working on expanding our library of Full Dome movies and presentations as well as opening up the planetarium to a wider variety of events than ever before.

In addition to our traditional presentations using our classic Star Machine, we are expanding our museum collection and exhibits to create a much more interactive experience of astronomy for our increasing number of visitors.

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