1957

Russia launches Sputnik 1 satellite.

In the U.S., Johns Hopkins Applied Physics Laboratory (APL) researchers find that a satellite orbit and the location of a fixed point can be predicted from each other using the satellite's Doppler frequency shift.

1959

The first Transit satellite is launched. A forerunner to GPS, Transit was developed by the Johns Hopkins APL to enable satellite navigation for marine applications. Position fixes take hours.

1967

The first U.S. Timation satellite is launched. Timation was another forerunner to GPS that proved the atomic frequency standards on-board satellites as well as other concepts for practical satellite navigation more.

The same year, the Transit system is made available to the civilian community.

1968

The Department of Defense (DoD) establishes a Navigation Satellite Executive Steering Group (NAVSEG) to coordinate the efforts of several satellite navigation groups.

1973

U.S. Air Force (USAF) designates a program manager to consolidate multiple satellite navigation concepts for all U.S. military services into a single system known as the Defense Navigation Satellite System. A GPS Joint Program Office (JPO) was established to lead this effort. The U.S. Government approves NAVSTAR GPS for development.

1978

First GPS satellite launched.

1983

Korean Airlines flight 007 strays over the Soviet Union and is shot down. President Reagan declares GPS will be available and free to all when operational to help prevent future navigation tragedies.

1984

The U.S. Department of Commerce's National Oceanic an Atmospheric Administration (NOAA) published the first geodetic standards that allow use of GPS data for mapping. Surveyors become early civilian GPS users due to dramatic productivity gains, despite limited satellite "in view" times.

Differential GPS and carrier-phase tracking capabilities are developed.

1986

Space Shuttle Challenger tragedy. Future GPS satellite launches delayed by 2 years. The Space Shuttle was the planned launch vehicle for GPS and satellites are moved to the Delta II rocket.

1987

DoD formally requests the Department of Transportation (DoT) to establish an office to respond to civil users' needs and to work closely with DoD to ensure proper implementation of GPS for civil use.

1988

GPS commercial dual-frequency user equipment introduced to the market.

1989

First GPS Block II satellite launched.

U.S. Coast Guard (USCG) becomes lead agency for interfacing with growing civilian GPS user communities.

1990

DoD activates Selective Availability (S/A).

1991

U.S. offer to make the GPS Standard Positioning Service (SPS) available beginning in 1993 to the international community on a continuous, worldwide basis free of direct user fees at the International Civil Aviation Organization's (ICAO) conference.

1990

Operation Desert Storm, the first major test of GPS in combat, creates unprecedented demand for GPS equipment.

1991

U.S. GPS manufacturers establish the U.S. GPS Industry Council (USGIC) as a technical information resource to governments, the public and media.

Real-time kinematic (RTK) technology developed.

1992

FAA issues performance standards for GPS receivers (TSO C129).

1993

GPS achieves Initial Operational Capacity (IOC) with full constellation of 24 GPS satellites providing continuous worldwide coverage.

1994

FAA recognizes GPS as operational for civil aviation use and is an integrated part of the U.S. air traffic control system. GPS is approved for use as a stand-alone navigation aid for all phases of flight through non-precision approach provided the GPS equipment meets TCO C129 criteria and is capable of Receiver Autonomous Integrity Monitoring (RAIM).

Development and installation of the Wide Area Augmentation System (WAAS) begins.

USCG's Navigation Center (NAVCEN) is commissioned.

1995

USAF Space Command announces the GPS system has met Full Operational Capability (FOC).

1996

Presidential Decision Directive (PDD) provides a comprehensive national policy on joint civil/military GPS management. S/A to be turned off by 2006.

1997

Congress embeds the policy principles of the GPS PDD into legislation that becomes public law signed by the President.

First Block IIR satellite launched.

1998

WAAS begins service; improves DGPS accuracy to 2 meters.

2000

S/A turned off. Autonomous accuracy improves from 100 meters to 12 meters.

2003

FAA commissions WAAS for aviation use.

2004

The President issues U.S. policy on Space-based Positioning Navigation and Timing (PNT). Joint U.S.-E.U. Agreement on GPS-Galileo Cooperation signed.

2005

First Block IIR-M satellite launched introduces a new L2C civilian signal and two new military signals.

2010

First Block IIF satellite launched introduces a new L5 signal.