1960: The U.S. Navy developed and successfully tested the first satellite (“Transit”) navigation system that today, still provides some service as a two-dimensional (horizontal) positioning system.

1967: The U.S. Navy developed the “Timation” satellite, which proved the ability to place accurate clocks in space (quartz, rubidium, and cesium) and was the precursor to the precise time capabilities of GPS as we know it today.

1973: GPS began as a test program using ground-based transmitters at the U. S. Army Proving Ground at Yuma, Arizona.

1976: Russia begins development of their satellite system “GLONASS”.

1978: The first U.S. experimental Block-I GPS satellite was launched.

1980s: GPS, although not yet fully operational and requiring careful planning for missions during times of satellite availability, was increasingly used by both U.S. military and civilian agencies. Land, air, and sea navigation, precise positioning, carrier phase survey techniques, and precise time and frequency dissemination were all accomplished to a limited extent during the initial phases of GPS deployment.

October 12, 1982: Russia adds numerous satellites to the GLONASS constellation.

1983: After Korean Airlines Flight 007 was shot down after straying into U.S.S.R.'s prohibited airspace, President Ronald Regan issued a direction making GPS freely available for civilian use once it was completed.

February 14, 1989: The first modern U.S. Block-II satellite was successfully launched.

1990: 43 U.S. laboratories requiring precise time were using GPS to synchronize their atomic clocks.

1994: 24 Block II and IIA operational GPS space vehicles (SVs) had been launched. The Block IIA SVs can store up to 14 days of uploaded data in case contact is lost with ground stations and can operate for 180 days with degraded navigation receiver performance. The next generation of space vehicles, the Block IIR SVs will

incorporate changes to include the capability of maintaining precise time. keeping without Control Segment uploads for periods of up to 210 days by exchanging data between GPS SVs.

December 1993: U.S. GPS achieved initial operational capability.

January 17, 1994: A complete constellation of 24 satellites was in orbit in the U.S..

1995: Russia’s GLONASS constellation is completed. Following completion, the system rapidly fell into disrepair with the collapse of the Russian economy.

April 1995: Full Operational Capability was declared by NAVSTAR in the U.S.

July 17, 1995: The U.S. Air Force announced that GPS had met all requirements for Full Operational Capability with 24 Block II SVs in orbit. With over 50 companies supplying a selection of over 275 GPS receivers to a global market, the well established user community of navigators, surveyors, geologists, geodesists, time and frequency users, and many thousands of recreational users has come to accept GPS as a viable military and worldwide civilian used system.

1996: Recognizing the importance of GPS to civilian users as well as military users, U.S. President Bill Clinton issued a policy directive declaring GPS to be a dual-use system (civil & military) and establishing an Interagency GPS Executive Board to manage it as a national asset.

1998: GPS technology was inducted into the U.S. Space Foundation Space Technology Hall of Fame.

May 2, 2000: "Selective Availability" was discontinued in the U.S. as a result of the 1996 executive order, allowing users to receive a non-degraded signal globally.

2001: Russia commits to restoring "GLONASS" navigation satellite system.

May 26, 2003: Germany, France, Italy, and the United Kingdom agree upon the Galileo satellite system for the European Union and European Space Agency. Galileo is primarily for civil use.