Thick fog envelops several Air Force KC-135 mid-air refueling aircraft on the flight line at the Iowa Air National Guard’s 185th Air Refueling Wing in Sioux City, Iowa in the early morning hours of Oct. 10, 2017. (Master Sgt. Vincent De Groot/U.S. Air National Guard)
A Wounded Warrior participant competes in the 33rd annual Army Ten Miler at Washington D.C., Md., Sep. 8, 2017. (Pfc. Miguel Pena/Army)
Sgt. Manuel Toledomeza (left), a section chief, and Lance Cpl. Anthony Miller, a gunner, both with 3rd Platoon, Rocket Battery F, 2nd Battalion, 14th Marine Regiment, Marine Forces Reserve, secure the wires of the High Mobility Artillery Rocket System to prevent any loose disturbance, at Landing Zone Bull Attack, near the Chocolate Mountain Aerial Gunnery Range, California, Oct. 11, 2017. (Lance Cpl. Melany Vasquez/Marine Corps)
Boatswain's Mate 2nd Class Carlos Cortes, left, and Seaman James G. Thompson hook cargo to an MH-60S Sea Hawk helicopter while conducting a vertical replenishment aboard the Arleigh Burke-class guided-missile destroyer USS Winston S. Churchill (DDG 81) during exercise Joint Warrior 17-2, Oct. 8, 2017. (Mass Communication Specialist 2nd Class Amy M. Ressler/Navy)
A U.S. Air Force F-35A Lightning II fighter aircraft lands on the flight line Oct. 12, 2017, at Eielson Air Force Base, Alaska. The F-35 is here to conduct cold weather testing to ensure the fifth generation multi-role fighter aircraft performs optimally in Alaska's harsh weather conditions. (Airman 1st Class Eric M. Fisher/Air Force)