Prague Planetarium

If the universe is an unreachable beyond, then the newly renovated Prague Planetarium stands as the closest point of contact—where the act of looking up brings us into intimate proximity with the stars. Recently completed by Czech architecture studio collcoll, the two-year overhaul transforms the historic building into a cutting-edge venue for immersive astronomical education and cultural experience.

Located within Stromovka Park—dubbed the “lungs of the city”—the Prague Planetarium was originally designed in 1950 by architect Jaroslav Frágner. Today, it emerges as the world’s largest LED dome planetarium, following a comprehensive upgrade that marries heritage preservation with state-of-the-art technology. At the heart of the redesign is a 22-meter-wide LED dome screen, developed in collaboration with COSM (USA), offering a breathtaking 45-million-pixel resolution. The installation redefines spatial perception, replacing passive viewing with a fully immersive encounter that envelops the audience in simulated cosmic depths and vivid galactic color.

To optimize circulation and visual focus, collcoll worked with heritage authorities to relocate the central Zeiss Jena projector, originally positioned in the main hall. The newly freed space was restructured into a stepped geometric formation that intuitively directs viewers’ gaze upward. Seating capacity was increased by 20%, bringing the total to 277 seats, all custom-developed with local manufacturers as ergonomic, adjustable recliners. Complemented by a concealed acoustic system behind the dome, the new configuration enhances the auditory and visual immersion—an experiential reinterpretation of the stargazing ritual.

The renovation extends beyond dome technology and seating. The entrance hall has been redesigned as an interactive environment, where a continuous ring-shaped LED screen replaces static exhibition displays to function as a dynamic multimedia platform. A new cloakroom improves visitor flow, and in summer months, the basement opens as a simulation and exhibition space. Outside, improved landscaping and a newly installed retail kiosk accompany the redesigned exit. Previously misplaced ramps were removed to create barrier-free access and a seamless visual connection between the architecture and the urban surroundings.

Recognizing the site's sensitive location within Stromovka Park's ecological core, the design also incorporates sustainable energy strategies. A cooling and heat recovery system is now integrated into the building, whereby heat generated during summer by the dome is stored in six geothermal wells, each reaching a depth of 200 meters. This stored thermal energy is repurposed for winter heating, offering both energy efficiency and environmental responsibility. In this way, the updated planetarium is not just a beacon for cosmological wonder, but also a model for sustainable adaptation of heritage architecture. Through collcoll’s synthesis of innovation and ecological stewardship, the Prague Planetarium becomes more than a place for observing stars—it becomes a place for embodying the cosmos, where visitors can feel, hear, and imagine the infinite mysteries of the universe.