Just got an announcement from the Dusseldorff tourism folks about a new exhibit, "Out of this World - Wonders of the Solar System."
The exhibit (actually in Oberhausen) explores the "cultural and artistic perspectives on the creation and death of our solar system in the vast dimensions of the cosmos." They've converted a giant "obsolete gas holder," called the Gasometer, into a huge building that contains a replica of the solar system, with the highlight being an 82-foot-wide replica of the moon.
Looks cool.
Moon
Gasometer
I'd go if I could afford to travel. If you read German, there's info at http://www.ruhrportal.de/sehenswuerdigkeiten-ausflugsziele/gasometer-oberhausen