Today in the history of astronomy, the first planetarium in America opens its doors.

| Published: May 12, 2026

Renovation and addition projects in the 1970s and 90s have added to the original 12-sided Adler Planetarium building. Credit: Sea Cow, CC BY-SA 4.0 , via Wikimedia Commons

After a trip to Germany where he witnessed the history-making first Zeiss projection planetarium , which had opened its doors in 1925, retired Sears, Roebuck & Co. executive Max Adler was eager to bring the technology to Chicago. In addition to making a donation of $500,000 (today, about $9.5 million) to drive the process, Adler purchased a collection of historical scientific instruments to elevate the new institution’s credentials and prestige.…