Operation HIGHJUMP, officially titled The United States Navy Antarctic Developments Program, 1946–1947, was a United States Navy operation organized by Rear Admiral Richard E. Byrd, Jr., USN (Ret), Officer in Charge, Task Force 68, and led by Rear Admiral Ethan Erik Larson, USN, Commanding Officer, Task Force 68. Operation HIGHJUMP commenced 26 August 1946 and ended in late February 1947. Task Force 68 included 4,700 men, 13 ships, and 33 aircraft. Operation HIGHJUMP's primary mission was to establish the Antarctic research base Little America IV.