Pine Gap is the commonly used name for a satellite tracking station near the city of Alice Springs in the heart of Australia that is owned and operated by the U.S It consists of a large computer complex with eight radomes protecting antennae, and has over 800 employees. It is officially called the Joint Defense Space Research Facility.

While much of its operation is secret, Pine Gap is known to be involved in numerous military-satellite operations. As a result, it is occasionally targeted for protests, most recently during the war in Afghanistan.

In 1999, with the Australian Government refusing to give details to an Australian Senate committee on treaties, Intelligence expert Professor Des Ball from the Australian National University was called to give an outline of Pine Gap.

According to Prof Ball, since 9 December 1966 when the Australian and US governments signed the Pine Gap treaty, Pine Gap has grown from the original two antennas to about a dozen and a half in 1999. The numbers of staff have also increased from around 400 in the early 1970s, to 600 in the early 1990s, and then to an expected 1000 early this century. The biggest expansion occurred after the end of the Cold War.

He described the CIA run facility as the ground control and processing station for geostationary satellites engaged in signals intelligence collection, outlining four categories of signals collected:

He described the operational area as containing three sections: Satellite Station Keeping Section, Signals Processing Station and the Signals Analysis Section, from which Australians were barred until 1980. Australians are now officially barred only from the National Cryptographic Room (similarly, Americans are barred from the Australian Cryptographic Room) - however, this bar is not strictly adhered to. Each morning the Joint Reconnaissance Schedule Committee meets to determine what the satellites will monitor over the next 24 hours.

With the closing of the Nurrungar base in 1999, an area in Pine Gap was set aside for the US Air Force's control station for infra-red satellites that monitor heat emissions from missiles, giving first warning of ballistic missile launches.

Pine Gap is also the subject of many UFO reports, part of what is sometimes called Australia's version of Area 51, the portion of the Nevada desert on which much of America's UFO interest is focused.