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GPS Satellite Orbits
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Orbits Data Browser Most orbit files can be found under the "products" data type using this data browser utility. Additional orbit files and related products are available by selecting "combinations" or "gfiles".
Orbits are also available via http or ftp:
SOPAC provides several GPS satellite orbit files and associated products. The "products" directory includes (note: YYYY=year, DDD=day-of-year, WWWW=gps weeek, D=day-of-week, Y=year in decade, HH=hour-of-day):
sp3 precise ephemeris orbits in sp3 format (e.g., sioWWWWD.sp3.Z)
earth orientation files (e.g., sioWWWWD.erp.Z)
sinex files (e.g., sioWWWWD.snx.Z
analysis summary files (e.g., sioWWWW7.sum.Z)
clock files derived by a variety of analysis centers
Orbits are available from IGS and all IGS analysis centers (sio, jpl, cod, ngs, emr, usn, cod and gfz). Filenaming conventions use the following, where 'xx' represents the first two letters of the IGS analysis center:
xxo: final orbits, available within 10 days after the end of the UT day (e.g., sioWWWWD.sp3.Z)
xxr: rapid orbits, available after 17 hours (e.g., sirWWWWD.sp3.Z)
xxu: ultra-rapid orbits, provided every three hours (e.g., siuWWWD_HH.sp3.Z)
The "gfiles" directory contains gfiles (e.g., gpggaY.DDD.Z), which are orbit files that can only be used in GAMIT GPS data processing.
More information on precise orbits in sp3 (ASCII) format is available in the following publications:
- NOAA Technical Report NOS 133 NGS 46, Extending the
National Geodetic Survey Standard Orbit Formats,
November 1989
- NGS Second Generation ASCII and Binary Formats and
Associated Interpolation Studies, Proceedings,
Twentieth General Assembly of the International Union
of Geodesy and Geophysics, Vienna, Austria, August
1991.
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