The atomic nucleus can be translated as "Kern" in German. But "Kernfrage" also means "key question". Radioactivity is one of the big topics of our times and very controversially discussed. Since its discovery it rewrote our history first as a miracle, then as a superpower, but also destroyer. Yet the topic still remains abstract and unknowable for many people. Through the interactive installation „Kernfrage“ visitors can literally get closer to radioactivity. In three areas, divided into three zones, they can discover various aspects of the topic auditory. Meanwhile, they are getting closer and closer to the origin of radioactivity.