Pituffik Space Base

Pituffik Space Base (, bee-doo-FEEK; Greenlandic: [pitufːik]; IATA: THU, ICAO: BGTL), formerly Thule Air Base (, TOO-lee), is a United States Space Force base located on the northwest coast of Greenland in the Kingdom of Denmark under a defense agreement between Denmark and the United States. Denmark was a founding member of NATO in 1949, and the 1951 Greenland Defense Agreement allowed the United States to operate the base under a NATO framework, as long as both Denmark and the United States remain NATO members. Under the agreement, the United States has exclusive jurisdiction over its facilities at the base, but with the Danish flag being required to be flown over the base alongside the American flag and the Danes having the right to station a consulting liaison officer at the base. The 1951 agreement was modified in 2004 to require that the Greenlandic flag also be flown over the base and gave the Greenlandic government the right to appoint a liaison officer for the base. As of 2025, about 150 United States service members are permanently stationed there, down from some 6,000 during the Cold War. It is the northernmost Department of Defense installation, 1,210 km (750 mi) north of the Arctic Circle and 1,524 km (947 mi) from the North Pole. Pituffik's Arctic environment includes icebergs in North Star Bay, two islands (Saunders Island and Wolstenholme Island), a polar ice sheet, and Wolstenholme Fjord. The base is home to a substantial portion of the global network of missile warning sensors of Space Delta 4, and space surveillance and space control sensors of Space Delta 2, providing space awareness and advanced missile detection capabilities to North American Aerospace Defense Command (NORAD), the United States Space Force, and joint partners. Pituffik Space Base is also home to the 821st Space...