PETERSON AIR FORCE BASE, Colo. -- Lt. Col. Roger Sherman accepted command of the 16th Space Control Squadron from Col. Nina Armagno, 21st Operations Group commander, April 22, 2011, at the Peterson Air and Space Museum. Colonel Sherman left Air Force Space Command to become the new leader at the 16th SPCS, replacing Lt. Col. Paul Tombarge, who assumed his new role as 21st OG deputy commander. (U.S. Air Force photo/Dennis Howk)