Space Photography By Colonel Douglas H. Wheelock

ISS Expedition 24
He was a flight engineer on ISS Expedition 24. Along with fellow astronaut Tracy Caldwell Dyson, he undertook an 8hr 3min spacewalk to repair a failed ammonia pump module on 7 August 2010.
ISS Expedition 25
On September 22, 2010 Wheelock took command of the International Space Station at the beginning of Expedition 25. He is the first U.S. Army officer to command the ISS.