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GPS NANUS, ALMANACS, OPS ADVISORIES, & SOF

For help on how to understand and/or interpret an Operational Advisory message, please visit our tutorial page.

Format of the messages

Almanacs, Operational Advisories, and NANUs are available for download in two formats:

  1. the original format in which the files are produced (.alm, .al3., .nnu, .oa1, and .sof)
  2. plain text (.txt)


OPS Advisories (GPS Status)

  • Current Operational Advisories - .oa1, .txt

Almanacs (YUMA & SEM)

  • Current YUMA Almanac - .alm, .txt
  • Current SEM Almanac - .al3, .txt
  • Definition of a YUMA Almanac can be found in the current version of Navstar GPS Control Segment to User Support Community Interfaces, ICD- GPS-240. You can find the document on the GPS Technical References page.
  • Definition of a SEM Almanac can be found in the current version of Navstar GPS Control Segment to User Support Community Interface, ICD- GPS-240. You can find the document on the GPS Technical References page.

NANUs

SATELLITE OUTAGE FILE (SOF)

  • Current SOF - .sof, .txt
  • Definition of the SOF can be found in the current version of Navstar GPS Control Segment to User Support Community Interfaces, ICD- GPS-240. You can find the document on the GPS Technical References page. Higher priority GPS Control Station operations may delay development and publication of the SOF after release of a NANU.

ARCHIVES

In order to aid customers that need to download the various almanac files on a regular or semi-regular basis or who would like to download some or all of the files for one or more years, we have developed a set of access points to allow the download of the files programmatically. Please read the instructions for programmatically downloading NANU, Almanac and Ops Advisory files.