GPS Timing Data & Information

Coordinated Universal Time (UTC) Time Step (Leap Second)

• As of January 1, 2009, 0H 0M 0S, GPS is ahead of UTC by fifteen (15) seconds.

Timing Data for Individual GPS Satellites

• USNO Format format explanation
• Most Recent 1 Day
• Most Recent 7 Days [UNIX compressed format] [PC zipped format]
• Most Recent 30 Days [UNIX compressed format] [PC zipped format]
• CGGTTS Format (Common-View) format explanation
• Most Recent 1 Day
• Most Recent 7 Days [UNIX compressed format] [PC zipped format]
• Most Recent 30 Days [UNIX compressed format] [PC zipped format]

• GPS Time vs. UTC via USNO Master Clock: [Most Recent 30 Days] [Most Recent 180 Days]

Notice Advisories to NAVSTAR Users (NANUs)

• 2011 NANUs [NANU Number index] [Satellite Number index]
• Most Recently Issued NANUs
• Current Constellation Status, Planned & Recent Outages
• 2010 NANUs [NANU Number index] [Satellite Number index]
• 2009 NANUs [NANU Number index] [Satellite Number index]
• 2008 NANUs [NANU Number index] [Satellite Number index]
• 2007 NANUs [NANU Number index] [Satellite Number index]
• 2006 NANUs [NANU Number index] [Satellite Number index]
• 2005 NANUs [NANU Number index] [Satellite Number index]
• 2004 NANUs [NANU Number index] [Satellite Number index]
• 2003 NANUs [NANU Number index] [Satellite Number index]
• 2002 NANUs [NANU Number index] [Satellite Number index]
• 2001 NANUs [NANU Number index] [Satellite Number index]
• 2000 NANUs [NANU Number index] [Satellite Number index]
• 1999 NANUs [NANU Number index] [Satellite Number index]
• 1998 NANUs [NANU Number index] [Satellite Number index]
• 1997 NANUs [NANU Number index] [Satellite Number index]
• 1996 NANUs [NANU Number index] [Satellite Number index]
• 1995 NANUs [NANU Number index]
• 1994 NANUs [NANU Number index]

General GPS Information

• GPS System Description
• Constellation Information
• Current Satellites
• Block I Satellites
• Block II Satellites
• Common-View Schedules
• Satellite Health Codes
• GPS Time Transfer Information

Links to Other GPS Web Sites

• Sources of GPS Data

  • GPS Almanacs from U.S. Coast Guard NAVCEN
  • GPS & Glonass NORAD Orbital Elements
  • NOAA's Space Environmental Data for navigational systems
  • International GPS Service for Geodynamics (IGS)
  
  

• Sources of GPS Information

  • Additional GPS Information: SA, DGPS, Leap Seconds, etc.
  • National Space-Based Positioning, Navigation, and Timing (PNT) Coordination Office
    • PNT website
    • PNT GPS website
  • GPS Page at the US Coast Guard Navigation Center
  • GPS Tutorials
  • University of Colorado
  • Trimble
  • Aerospace Corporation
  • GPS Joint Program Office (JPO)
  • GPS References, Acronyms, Glossary and Tutorial at GPS World
  
  

• Sources of GLONASS Information

• GLONASS Page of the Russian Space Agency Information-Analytical Centre
• GLONASS Constellation Status Page of the Russian Space Agency Information-Analytical Centre
• GLONASS Summary Page of Space and Tech



• Sources of Galileo Information

• Galileo Page of the European Space Agency

US Naval Observatory Home Page
What Time Is It? USNO Time Service Home Page
GPS Home Page at USNO