• The first modern planetarium opened in Munich, Germany on May 7, 1925, revolutionizing how people experienced and learned about astronomy.
• Planetarium technology has evolved significantly, from early opto-mechanical projectors to current digital systems offering immersive 360-degree experiences.
• Planetariums continue to play a vital role in astronomy education and public engagement, adapting to incorporate new data and discoveries.

This year marks the 100th anniversary of the first modern planetarium, which opened at the Deutsches Museum in Munich on May 7, 1925. This groundbreaking invention brought the stars indoors, allowing audiences to experience the night sky regardless of weather or light pollution. From the initial opto-mechanical projectors to today's advanced digital systems, planetariums have continually evolved, offering increasingly realistic and immersive simulations of the cosmos, significantly impacting astronomy education and public outreach.

• What: The 100th anniversary of the first modern planetarium is being celebrated with special events and programs worldwide.
• Who: Key figures include Oskar von Miller, first director of the Deutsches Museum, and the Carl Zeiss AG company, which built the first planetarium projector. Important planetariums mentioned are the Deutsches Museum (Munich), Melbourne Planetarium, Cejka Planetarium (IUP) and Auckland’s Stardome Observatory.
• When: The first modern planetarium opened on May 7, 1925. IUP’s Cejka Planetarium's program is on Wednesday at 7 p.m.
• Where: The first modern planetarium opened at the Deutsches Museum in Munich, Germany. Celebrations are occurring at planetariums worldwide, including IUP's Cejka Planetarium in Pennsylvania.

The centennial of the planetarium marks a significant milestone in the history of astronomy education and public engagement. From its humble beginnings as a mechanical projection device, the planetarium has evolved into a sophisticated tool for simulating the cosmos. The transition from opto-mechanical projectors to digital systems has expanded the capabilities of planetariums, allowing for immersive experiences and the exploration of vast datasets from telescopes and space agencies. This anniversary provides an opportunity to reflect on the planetarium's enduring impact on inspiring curiosity and fostering a deeper understanding of the universe.

The 100th anniversary of the planetarium is a testament to the enduring human fascination with the cosmos. From the pioneering efforts at the Deutsches Museum to the advanced digital planetariums of today, these institutions have played a crucial role in making astronomy accessible and engaging for people of all ages. As technology continues to advance, planetariums will likely remain vital hubs for education, exploration, and inspiration, fostering a deeper connection to the universe around us.