Timation

TheNaval Research Laboratory’s managers for the Timation program and, later, the GPS program:Roger L. Easton(left) andAl Bartholomew.

Timation I (rectangular object in center of photo), launched May 31, 1967, tested in a "piggyback" launch aboard an Air Force Thor-Agena D rocket

TheTimationsatelliteswere conceived, developed, and launched by theUnited States Naval Research LaboratoryinWashington, D.C.beginning in 1964. The concept of Timation was to broadcast an accurate time reference for use as a ranging signal to receivers on the ground. On 31 May 1967, theTimation-1satellite was launched. This was followed by theTimation-2satellite launch in 1969. The results of this program and Air Force Project 621B formed the basis for theGlobal Positioning System(GPS). The Navy's contribution to the GPS program continued to be focused on ever more accurate clocks.

History

There is a historical connection between accurate time keeping, navigation, and theNavy.In 1714, theBritish governmentpassed theLongitude Act(seelongitude prize) to create an incentive to solve the problem of navigation at sea. The solution, developed byJohn Harrison,was an accurate clock which could compare local time toGreenwich,England time. To this day,Coordinated Universal Time(UTC), the successor ofGreenwich Mean Time(GMT), is the reference time for the planet, and in theUnited States,the official time for theDepartment of Defense(DoD) is kept by theUnited States Navyat theU.S. Naval Observatoryin Washington, D.C. This is kept insynchronizationwith the official civilian time reference maintained byNational Institute of Standards and Technology(NIST) and contributes to theInternational Atomic Time.

See also

• Time signal
• Global Positioning System(GPS)

External links

• Timation Satellite Program (navy.mil)Archived30 June 2008 at theWayback Machine
• Who invented the Global Positioning System? (thespacereview.com)
• Range navigation using the Timation II satellite