Frank De Winne and Robert Thirsk participate in life support system training at NASA's JSC

ESA astronaut Frank De Winne (background), Expedition 20 flight engineer and Expedition 21 commander; and Canadian Space Agency astronaut Robert Thirsk, Expedition 20/21 flight engineer, participate in an Environmental Control and Life Support System (ECLSS) training session in the International Space Station Destiny laboratory mock-up/trainer in the Space Vehicle Mock-up Facility at NASA's Johnson Space Center.