Epner Technology, Inc. gold plated a Sorption Cooler component for a PLANCK mission under Jet Propulsion Laboratories (JPL). To achieve 20° Kelvin on this key PLANCK component, this device uses hydride material to pressurize and/or evacuate hydrogen gas. The two-part compressor element isolates hot from cold and functions as a gas gap switch. The bore of the outer element (approx. 400 mm long) is highly polished, nickel plated and then re-polished prior to Laser Gold plating 2.5 microns thick. The exterior of the inner element was treated similarly.
Pre-manufacturing tests at JPL indicated Laser Gold had achieved the theoretical emissivity of pure, evaporated gold. This data was confirmed in the production product.