Stock Photo Description: Stock photo of U.S. Army soldiers, assigned to 3rd Battalion, 157th Field Artillery, Colorado Army National Guard, lighting up the range with tracer rounds as they fire the M-240B medium machine gun with the help of night optics at Fort Hood, Texas, on April 25, 2009. The battalion, which arrived at its mobilization station on April 18, is deploying this summer in support of Operation Iraqi Freedom. DoD photo by Staff Sgt. Liesl Marelli, U.S. Army. (Released). Stock photography by Department of Defense Public Domain.