A cooperative and playful approach to scientific topics and questions is the goal of the enhancement of planetariums to interactive knowledge theatres. The prototype of a group-controlled simulation theater is currently being developed in cooperation between the design studio Halbautomaten Communication Design and the Carl-Zeiss-Planetarium in Stuttgart, Germany. The project is subsidized by the "Digital Content Funding" of the Baden-Württemberg Medien- und Filmgesellschaft (MFG).