Pituffik Space Base
NearQaanaaq,Avannaata in Greenland
Aerial view of the base withSaunders Island in the background andMount Dundas at right
Shield ofSpace Base Delta 1
Site information
Type	Military base
Operator	United States Space Force
Controlled by	Space Base Delta 1
Condition	Operational
Location
Pituffik Space Base Location in Greenland Show map of Greenland Pituffik Space Base Location in the Arctic Circle Show map of Arctic
Coordinates	76°31′52″N68°42′11″W / 76.53111°N 68.70306°W /76.53111; -68.70306 (Pituffik Space Base)
Site history
Built	1943 (1943)
In use	1943–present
Events	B-52 crash (1968)
Garrison information
Current commander	Colonel Shawn Lee[1][2]
Garrison	821st Space Base Group
Airfield information
Identifiers	IATA: THU,ICAO: BGTL,WMO: 042020
Elevation	76.5 metres (251 ft)AMSL
Runways Direction Length and surface 08T/26T 3,047 metres (9,997 ft) Asphalt
Source: DanishAIS[3]

Pituffik Space Base (/biːduːˈfiːk/bee-doo-FEEK;^[4]Greenlandic:[pitufːik];IATA:THU,ICAO:BGTL), formerlyThule Air Base (/ˈtuːliː/), is aUnited States Space Force base located on the northwest coast ofGreenland in theKingdom of Denmark under a defense agreement between Denmark and theUnited States. Currently, 150 United States service members are stationed there, after the United States significantly reduced its presence from 6000 personnel during theCold War.^[5] Denmark was a founding member ofNATO 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, theDanish national flag must be flown at the base to recognize that the base is on Danish territory, but the United States is allowed to fly its own flag alongside the Danish flag on the facilities it operates.

It is the northernmostDepartment of Defense installation, 1,210 km (750 mi) north of theArctic Circle and 1,524 km (947 mi) from theNorth Pole. Pituffik's Arctic environment includes icebergs inNorth Star Bay, two islands (Saunders Island andWolstenholme Island), a polar ice sheet, andWolstenholme Fjord. The base is home to a substantial portion of the global network of missile warning sensors ofSpace Delta 4, and space surveillance and space control sensors ofSpace Delta 2, providing space awareness and advanced missile detection capabilities toNorth American Aerospace Defense Command (NORAD), the United States Space Force, and joint partners.

Pituffik Space Base is also home to the 821st Space Base Group and is responsible for space base support within the Pituffik Defense Area for the multinational "Team Pituffik" population. The base hosts the12th Space Warning Squadron (12 SWS), which operates aBallistic Missile Early Warning System (BMEWS) designed to detect and trackICBMs launched against North America. The base is also host to Detachment 1 of the23rd Space Operations Squadron, part of theSpace Delta 6's global satellite control network. The airfield's 3,000 m (10,000 ft) runway handles more than 3,000 US and international flights per year. The base is also home to the northernmost deep water port in the world.^[6]

Pituffik Space Base has previously served as the regional hub for nearby installations, includingCape Atholl (LORAN station),Camp Century (Ice Cap Camp),Camp TUTO (Ice Cap Approach Ramp and Airstrip), Sites 1 and 2 (Ice Cap Radar Stations), P-Mountain (radar and communications site), J-Site (BMEWS), North and South Mountains (research sites), and a research rocket firing site.^{[not verified in body]} It also was essential in the construction and resupply of High Arctic weather stations, includingCFS Alert (Alert Airport) andStation Nord.^{[citation needed]}

In 1818, SirJohn Ross's expedition made first contact with nomadicInughuit in the area.James Saunders's expedition aboardHMSNorth Star was marooned inNorth Star Bay in 1849–50 and named landmarks.^[7] In 1910 explorerKnud Rasmussen established a missionary and trading post there. He called the site "Thule" after classicalultima Thule; the Inuit called itUmanaq orUummannaq ("heart-shaped"), and the site is commonly called "Dundas" today. Whaling captain, explorer, and ethnologistGeorge Comer discovered a midden, dubbedComer's Midden, at Umanaq in 1916, and an archaeological excavation subsequently revealed a village of the proto-Inuit who came to be called theThule people. The United States abandoned its territorial claims in the area in 1917 in connection with the purchase of theVirgin Islands. Denmark assumed control of the village in 1937.

A cluster of huts known asPituffik ("the place the dogs are tied") stood on the wide plain where the base was built in 1951; a main base street was named Pituffik Boulevard. The population wasforcibly relocated to Thule. Later in 1953, the USAF planned to construct an air defense site near that village, and in order to limit contact with soldiers, the Danish government again relocated 130 inhabitants of "Old Thule", settling them 97 km (60 mi) north in a newly constructed village also named Thule (colloquially "New Thule", nowQaanaaq).

In a Danish Supreme Court judgment of 28 November 2003, the move was considered anexpropriative intervention. During the proceedings, the Danish government recognized that the movement was a serious interference and an unlawful act against the local population. The Thule tribe was awarded damages of 500,000kroner, and the individual members of the tribe who had been exposed to the transfer were granted compensation of 15,000 or 25,000 each. A Danish radio station continued to operate at Dundas, and the abandoned houses remained. The USAF only used that site for about a decade and has since returned to civilian use.

Knud Rasmussen was the first to recognize the Pituffik Plain as ideal for an airport. USAAF ColonelBernt Balchen, who builtSondrestrom Air Base, knew Rasmussen and his idea. Balchen led a flight of twoConsolidated PBY Catalina flying boats to Thule on 24 August 1942 and then sent a report advocating an air base toUSAAF chiefHenry "Hap" Arnold. However, the 1951 air base site is a few kilometers inland from the original 1946 airstrip and across the bay from the historical Thule settlement, to which an ice road connects it. The joint Danish-American defense area, designated by treaty, also occupies considerable inland territory in addition to the air base itself.^[8]

After theGerman occupation of Denmark on 9 April 1940,Henrik Kauffmann, Danish Ambassador to the United States, agreed "In the name of the king" with the United States, authorizing the United States to defend the Danish colonies on Greenland from German aggression. This agreement faced Kauffmann with a charge ofhigh treason by theprotectorate Government. Beginning in the summer of 1941, the United States Coast Guard and the War Department established weather and radio stations atNarsarsuaq Airport (Bluie West-1),Sondrestrom Air Base (Bluie West-8), Ikateq (Bluie East Two), andGronnedal (Bluie West-9). In 1943 theArmy Air Forces set upweather stationsScoresbysund (Bluie East-3) on the east coast around the southern tip of Greenland, and Thule (Bluie West-6) to be operated by Danish personnel. Many other sites were set up, but BW-6, isolated in the far North, was then of very minor importance.^[9]

After liberation, Denmark ratified the Kauffmann treaty but began efforts to take over US installations. Nonetheless, in the summer of 1946, the radio and weather station was enhanced with a gravel airstrip and an upper-air (balloon) observatory. This was part of an American-Canadian initiative to construct joint weather stations in the High Arctic. This station was under joint US-Danish operation. The location changed from the Thule (Dundas) civilian village to mainland Pituffik. From 1946 to 1951, the airstrip played an important role in Arctic resupply, aerial mapping, research, and search-and-rescue.

The treaty's ratification in 1951 did not change much, except that theDanish national flag must be side by side with theUS national flag on the base.

In 1949, Denmark joined theNorth Atlantic Treaty Organization (NATO) and abandoned its attempt to remove the United States bases. By the outbreak of theKorean War next year, the USAF embarked on a global program of base-building in which Thule (at the time) would be considered the crown jewel owing to its location across the Pole from theSoviet Union, as well as its merit of being the northernmost port to be reliably resupplied by ship. Thule became a key point in American nuclear retaliation strategy.Strategic Air Command (SAC) bombers flying over theArctic presented less risk of early warning than using bases in the United Kingdom. Defensively, Thule could serve as a base for intercepting bomber attacks along the northeastern approaches to Canada and the United States.

A board of Air Force officers headed byGordon P. Saville recommended pursuing a base at Thule in November 1950. It was subsequently supported by theJoint Chiefs of Staff and approved byPresident Truman. To replace the agreement entered into during World War II between the US and Denmark, a new agreement concerning Greenland was ratified on 27 April 1951 (effective on 8 June 1951). At the request of NATO, the agreement became a part of the NATO defense program. The pact specified that the two nations would arrange for the use of facilities in Greenland by NATO forces in defense of the NATO area known as the Greenland Defense Area.

Thule Air Base was constructed in secret under the code nameOperation Blue Jay, but the project was made public in September 1952. Construction for Thule Air Base began in 1951 and was completed in 1953. The construction of Thule is said to have been comparable in scale to the enormous effort required to build thePanama Canal.^[10] TheUnited States Navy transported the bulk of men, supplies, and equipment from the naval shipyards inNorfolk, Virginia. On 6 June 1951, an armada of 120 ships sailed fromNaval Station Norfolk. On board were 12,000 men and 300,000 tons of cargo. They arrived at Thule on 9 July 1951. Construction, aided by continuous daylight in summer, took place around the clock. The workers lived on board the ships until quarters were built. Once they moved into the quarters, the ships returned home.

On 16 June 1951, the base was accidentally discovered by French cultural anthropologist and geographerJean Malaurie and his Inuit friend Kutikitsoq, on their way back from the geomagnetic North Pole.^[11]

Originally established as a Strategic Air Command installation, Thule periodically served as a dispersal base forB-36 Peacemaker andB-47 Stratojet aircraft during the 1950s. It also provided an ideal site to test the operability and maintainability of these weapon systems in extreme cold weather. Similar operations were also conducted withB-52 Stratofortress aircraft in the 1950s and 1960s.

In 1954, the 378 m (1,240 ft)Globecom Tower, a tower for military radio communication, was built at Northmountain. At the time of its completion, it was the third tallest human-made structure on earth^{[citation needed]} and the tallest structure north of the Arctic Circle in the Western hemisphere.

In the winter of 1956–1957, threeKC-97tankers and alternately one of twoRB-47H aircraft made polar flights to inspect Soviet defenses. Five KC-97s were prepared for flight with engines running in temperatures of −46 °C (−50 °F) to ensure three could achieve airborne status. After a two-hour head start, a B-47 would catch up with them at the northeast coastline of Greenland where two would offload fuel to top off the B-47's tanks (the third was an air spare). The B-47 would then fly seven hours of reconnaissance, while the tankers would return to Thule, refuel, and three would again fly to rendezvous with the returning B-47 at northeast Greenland. The B-47 averaged ten hours and 4,500 km (2,800 mi) in the air, unless unpredictable weather closed Thule. In that case, the three tankers and the B-47 had to additionally fly to one of three equidistant alternates: England,Alaska, orLabrador. This sometimes occurred in moonless, 24-hourArctic darkness, December through February. These flights demonstrated the capabilities of the USStrategic Air Command toSoviet Anti-Air Defense.

In 1959, the airbase was the main staging point for the construction ofCamp Century, some 240 km (150 mi) from the base.^[12] Carved into the ice, and powered by anuclear reactor,PM-2A Camp Century was officially a scientific research base, but in reality was the site of the top secretProject Iceworm. The camp operated from 1959 until 1967.

In the late 1950s, theDEW 1 to 4 were built as "weather stations". Thule Air Base would act as a supply station for the DYE bases.^{[citation needed]}

In 1957, construction began on fourNike Missile sites around the base, and they and their radar systems were operational by the end of 1958.

In 1961, a Ballistic Missile Early Warning System (BMEWS) radar was constructed at "J-Site", 21 km (13 mi) northeast of the main base. BMEWS was developed by theRCA Corporation to warn North America of a transpolar missile attack from the Russian mainland and submarine-launched missiles from the Arctic and North Atlantic oceans. At this time, Thule was at its peak, with a population of about 10,000. Starting in July 1965, activities at Thule were generally downsized. The base host unit, the4683d Air Defense Wing, was discontinued. By January 1968, the population of Thule was down to 3,370. On 21 January 1968, a B-52G bomber carrying four nuclear weaponscrashed just outside Thule.

Thule is the location where the fastest recorded sea level surface wind speed in the world was measured when a peak speed of 333 km/h (207 mph) was recorded on 8 March 1972, immediately prior to the instrument's destruction.^[13][14]

Thule became an Air Force Space Command base in 1982. The US and Denmark agreed to reduce the base to half its original area on 30 September 1986.^[15] It was home to the 821st Space Base Group, which exercised air base support responsibilities within the Thule Defense Area. The base hosts the12th Space Warning Squadron (21st Operations Group, 21st Space Wing), a Ballistic Missile Early Warning Site designed to detect and track ICBMs launched against North America. Missile warning and space surveillance information flows to NORAD command centers located atPeterson Space Force Base,Colorado. Thule is also host to Detachment 1 of the23rd Space Operations Squadron, part of the50th Space Wing's global satellite control network, as well as operating many new weapons systems. In addition, the airfield boasts a 3,047 by 42 m (9,997 by 138 ft) asphalt runway, with 3,000 US and international flights per year.

The Dundas Peninsula, including Old Thule and Uummannaq, was relinquished by the US and returned to Danish jurisdiction on 20 February 2003.^[16][17] A delegation from theNATO Parliamentary Assembly visited Thule in early September 2010 and were told by the base commander that, at that time (summer), approximately 600 personnel were serving at Thule, a mix of mostly US and Danish active duty personnel and contractors.^[18]

There is only a brief period each year in the summer when sea ice thins sufficiently to send supply ships to the base. The US sends one heavy supply ship each summer in what is calledOperation Pacer Goose.^[19]

In 2020, Thule Air Base was formally transferred to theUnited States Space Force. On 6 April 2023, Thule was renamed Pituffik Space Base, reflecting its status as a Space Force base and the native name for the region.^[4][20]

On 28 March 2025, Vice PresidentJD Vance, his wifeUsha, andMike Waltz, the national security adviser, toured the base, as part of a trip arranged by theTrump administration. Vance was the most senior US government official ever to visit the base. The visit came during a time of renewed discussion of theproposed acquisition of Greenland by PresidentDonald Trump^[21] and was opposed by Greenlanders.^[22] On 11 April 2025, the base commander, Colonel Susannah Meyers, was relieved of command by the Trump administration for "undermining" Vice President Vance after his visit by sending an email to base personnel (staffed by Americans, Canadians, Danes, and Greenlanders) that included: "I spent the weekend thinking about Friday's visit [by VP Vance]—the actions taken, the words spoken, and how it must have affected each of you. I do not presume to understand current politics, but what I do know is the concerns of the US administration discussed by Vice President Vance on Friday are not reflective of Pituffik Space Base. I commit that, for as long as I am lucky enough to lead this base, all of our flags will fly proudly—together".^{[23][24][25][26]}

• Northeast Air Command, 1 July 1951 – 1 April 1957
• Strategic Air Command

  Eighth Air Force, 1 April 1957 – 1 July 1960

• Air Defense Command (later redesignated Aerospace Defense Command) 15 January 1968, 1 July 1960 – 1 December 1979
• Strategic Air Command, 1 December 1979 – 30 September 1992
• Air Force Space Command, 30 September 1992 – 20 December 2019
• United States Space Force, 20 December 2019 – Present

Sources for major commands and major units assigned:^{[27][28][29][30][31]}

• 4th Battalion,55th Artillery, 1 Sep 1958 – 20 Dec 1965. (Nike)^[32]
• 7th Anti-Aircraft Artillery Group, 1 July 1955 – 20 December 1965 (Redesignated 7th Artillery Group 20 March 1958) [A, B, C, and D Batteries 90mm AAA cannon; 549th 75mm AAA BN (Sky Sweeper); 51st Ordnance Company]^[32]

Thule Tracking Station (TTS) is operated by Pituffik Space Base, using the callsign POGO. The station76°30′57″N68°36′0″W / 76.51583°N 68.60000°W /76.51583; -68.60000) is a US Space Force installation in Greenland, near the base, and has aRemote Tracking Station (callsign: Polar Orbiting Geophysical Observatory (POGO)) of the Satellite Control Network.^[33]

It was originally the classified6594th Test Wing's Operating Location 5 designated byAir Force Systems Command on 15 October 1961: the station was operational on 30 March 1962, with "transportable antenna vans parked in an oldStrategic Air Command bomb assembly building."^[33]The permanent RTS equipment was emplaced in 1964,^[33] and a communications terminal was emplaced on Pingarssuit Mountain—Thule Site N-32^[34] (moved toThule Site J in 1983.^[33]

Notable units based at Pituffik Space Base:^[35]

Space Operations Command

• Space Base Delta 1
  • 821st Space Base Group
    • 821st Support Squadron
    • 821st Security Forces Squadron
• Space Delta 4
  • 12th Space Warning Squadron
• Space Delta 6
  • 23rd Space Operations Squadron
    • Detachment 1

To assist with port operations, Pituffik is home to the only tugboat in the Department of the Air Force, the 71-footRising Star (USAF TG-71-9001).^[36] In the summertime, theRising Star escorts fuel tankers and cargo ships, aligns them with the pier, and moves icebergs out of the way as vessels enter North Star Bay. It is also used for sightseeing tours of the surrounding bays and fjords during the summer. In the winter, it is hauled onto shore. In 2020, the tugboat was used to save a sinking ship and its crew of six 50 kilometers (31 mi) south of base, towing the distressed ship back to the port at Pituffik.^[37]

In 1954, aDouglas C-124C Globemaster II operated by the US Air Force crashed on approach to the air base, killing ten people.^[38]

On 21 January 1968, aB-52G Stratofortress from the380th Strategic Aerospace Wing,Plattsburgh Air Force Base, New York, on a secret airborne nuclear alert crashed and burned on the ice near Thule Air Base. The impact detonated thehigh explosives in the primary units of all four of theB28 nuclear bombs it carried, but nuclear andthermonuclear reactions did not take place due to thePAL andfail-safe mechanisms in the weapons, thus preventing the actual detonation of the weapons themselves. The resulting fire caused extensiveradioactive contamination.^[39] More than 700 Danish civilians and US military personnel worked under hazardous conditions, the former without protective gear, to clean up the nuclear material.^[40] In 1987, nearly 200 Danish workers tried unsuccessfully to sue the United States. Kaare Ulbak, chief consultant to the Danish National Institute of Radiation Hygiene, said Denmark had carefully studied the health of the Thule workers and found no evidence of increased mortality or cancer.^[41][42][43]

The Pentagon maintained that all four weapons had been destroyed. Although many of the details of the accident are still classified, some information was released by the US authorities under theFreedom of Information Act. After reviewing these files, an investigative reporter fromBBC News claimed in May 2007 that the USAF was unable to account for one of the weapons.^[40] In 2009, the assertions of the BBC were refuted by a Danish report after a review of the available declassified documentation.^[44]

As of 2010^[update], one airline provided commercial service to Pituffik.^[45]

Schuyler Line Navigation Company, a US flag ocean carrier, provides ocean transportation. Schuyler Line operates under a government contract to supply sustainment and building supplies to the base.^[46]

Pituffik has atundraclimate (ET) with long, severely cold winters lasting most of the year and short and cool summers. Precipitation is very low year round, but peaks during summer. The structures of the base are built onpermafrost, which makes them vulnerable to the effects ofclimate change.^[47]

Pituffik Space Base is depicted in the 2023 documentary filmThe Color of Ice,^[48] which follows scientists testing a hot-tip drill to melt into the ice sheet at the edge of the base.^[49] The film highlights how the ice-sheet surface at TUTO Ramp Road, which was built byUnited States Army Corps of Engineers for ice-sheet access toCamp Century in the 1960s, has melted downwards by almost 100 feet (30 m). Pituffik Space Base itself is arguably presented as aliminal space in the film.

• Annoatok
• Camp Fistclench
• Eastern Air Defense Force (Air Defense Command)
• Etah, Greenland
• Gerald Gustafson
• Guantanamo Bay Naval Base, an American base in Cuba with a similar lease agreement
• Kee Bird

• Ackrén, Maria (2019). "From bilateral to trilateral agreement: The case of Thule Air Base."Arctic Yearbook 2019.
• Dragsdahl, Joergen (2005)."US-Danish politics on Thule Air Base: A few dilemmas bypassed in Denmark and Greenland". Contemporary Security Policy.

Wikimedia Commons has media related toPituffik Space Base.

• Pituffik Space Base —Space Base Delta 1
• Thule Air Base at theWayback Machine (archived October 4, 2002)
• Accident history for THU atAviation Safety Network
• The short filmBig Picture: Arctic Night is available for free viewing and download at theInternet Archive.
• The short filmBig Picture: Operation Blue Jay is available for free viewing and download at theInternet Archive.

• Pituffik Space Base
• Installations of the United States Air Force in Greenland
• Airports in Greenland
• Baffin Bay
• Airfields of the United States Army Air Forces in Greenland
• Installations of Strategic Air Command
• Military airbases established in 1953
• 1953 establishments in Denmark
• 1950s establishments in Greenland

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