The reduced SMOS Structural Thermal Model in the Large Space Simulator. The central hexagonal body (called the hub) and one deployed arm consisting of three segments are clearly visible. The white colour results from the radio-frequency transparent Germanium-coated foil used to reflect solar illumination. The gold covered items are the equipment needed to change the orientation of the test item with respect to the simulated Sun. This equipment is connected mechanically to the support beam, which suspends the arm segment under normal gravity.