The High-Vacuum Plume Test Facility of Chemical Thrusters (STG-CT) at the DLR Institute of Aerodynamics and Flow Technology in Göttingen is a unique cryogenic vacuum facility, where spacecraft thrusters can be operated and investigated under space-like vacuum conditions (< 10 -5 mbar). View into the testing room. In the foreground lies the rear view of the engine. Electronics and fuel lines have to be heated. The insulation foil protects the cold walls from the radiated heat.