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Current GPS Constellation

Satellites in operation


  • The current GPS constellation consists of 31 Block II/IIA/IIR/IIR-M/IIF satellites.
  • GPS constellation and individual satellite status is updated every working day.
  • Block I are referred to as the original concept validation satellites developed by Rockwell International and reflect various stages of system development.
  • The first Block II satellite was launched in February 1989; the most recent Block IIF satellite was launched on May 15, 2013.

    USNO Master Clock Time
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