Departing Commander in Chief President Barack Obama salutes the troops during an armed forces full honor farewell ceremony at Joint Base Myer-Henderson Hall, Virgina, Jan. 4, 2017. Military members from across the services took part in the event, which included Defense Secretary Ash Carter and the chairman of the Joint Chiefs of Staff, Marine Corps Gen. Joe Dunford. Senior defense leaders thanked Obama for his accomplishments over the past eight years in protecting the nation and supporting the military. Army photo by Pvt. Gabriel A. Silva Air Force Senior Airman Carlos Aleman and Tech. Sgt. Craig Slaten use an auger to drill a hole into the frozen Tanana River in Fairbanks, Alaska, Dec. 5, 2016. The airmen drill into the ice to expose water, which allows the ice to build and create a stable bridge for transportation of equipment and supplies. Air Force photo by Airman 1st Class Cassandra Whitman U.S. Army Capt. (Dr.) Aaron J. Vandenbos, an orthopedic surgeon with the 67th Forward Surgical Team, attempts to evade the attack of a military working dog Dec. 7, 2016. U.S. Army photo by Maj. Chris N. Angeles Soldiers fire an M777A2 howitzer at night in support of Iraqi security forces at Platoon Assembly Area 14, Iraq, Dec. 7, 2016. They are assigned to Charlie Battery, 1st Battalion, 320th Field Artillery Regiment, 2nd Brigade Combat Team, 101st Airborne Division. The fire mission was in support of Combined Joint Task Force-Operation Inherent Resolve, the global coalition to defeat ISIL in Iraq and Syria. Photo by Spc. Christopher Brecht Navy Petty Officer 1st Class Jeremy Parrish signals to the pilot of an F/A-18E Super Hornet on the flight deck of the USS Dwight D. Eisenhower in the Mediterranean Sea, Dec. 10, 2016. The Hornet is assigned to Strike Fighter Squadron 86. The aircraft carrier was supporting U.S. national security interests in Europe. Navy photo by Petty Officer 3rd Class Nathan T. Beard Soldiers prepare to connect a high-density load to the belly of a UH-60 Black Hawk helicopter during slingload training at Fort Bragg, North Carolina, Dec. 7, 2016. The soldiers are assigned to 127th Engineer Battalion, 1st Brigade Combat Team. The helicopter is assigned to the 82nd Airborne Division's 82nd Combat Aviation. Army photo by Sgt. Steven Galimore The Navy's most technologically advanced surface ship USS Zumwalt (DDG 1000) steams in formation with USS Independence (LCS 2) and USS Bunker Hill (CG 52) on the final leg of her three-month journey to her new homeport in San Diego, Dec. 8, 2016. Upon arrival, Zumwalt will begin installation of her combat systems, testing and evaluation, and operation integration with the fleet. U.S. Navy Combat Camera photo by Petty Officer 1st Class Ace Rheaume Paratroopers practice door-breaching techniques during the Urban Mobility Breacher Course at Joint Base Elmendorf-Richardson, Alaska, Dec. 13, 2016. They are with 6th Brigade Engineer Battalion, 4th Infantry Brigade Combat Team (Airborne), 25th Infantry Division. Photo by Spec. Donald Williams As snow streams down, sailors change a prop on an EP-3E Aries II aircraft during a night check at Naval Air Station Whidbey Island in Oak Harbor, Washington, Dec. 11, 2016. The sailors are assigned to Fleet Air Reconnaissance Squadron 1. The aircraft provides fleet and theater commanders worldwide with real-time tactical signals intelligence and motion video intelligence. U.S. Navy photo Soldiers jump over the fire pit obstacle while participating in the Rubicon Command Team Challenge at Fort Jackson, South Carolina, Dec. 9, 2016. Army photo by Sgt. 1st Class Brian Hamilton