GPS satellite outages are determined by the US Space Force using a Notice Advisory to Navstar Users (NANU). NANUs are categorized by their type and can represent forecasted, current or summary outages. See the full list of outage types on the CelesTrak website.
NOTE: The Satellite Outage File supplied by 2SOPS and made available to the public on the NAVCEN website has inconsistencies. I have worked with Analytical Graphics Inc. to produce a consistent Satellite Outage File. I use this consistent file to display the outages on this page. Please contact me to learn more about how this file was modified.
GPS satellite outages identified as current by the US Space Force. Current outage types are usually reserved for unscheduled outages.
There are no current outages at this time.
GPS satellite outages identified as predicted by the US Space Force.
There are no predicted outages at this time.
GPS satellite outages identified as historical by the US Space Force, occurring within the last month.
|PRN||SVN||NANU||Type||Outage start||Outage stop||Duration|
|18||75||2022023||FCSTSUMM||May 19, 2022 20:19:00||May 20, 2022 02:03:00||00d:05h:44m:000s|
Last checked for outage data: 2022-05-22 20:43:46Z
ICD-GPS-240C defines the Satellite Outage File fields in Section 30: Appendix 3. In that section, specific NANU types are associated with specific Satellite Outage File states; Historical, Predicted and Current. In the currently published satellite outage files, there is a NANU type that is not covered: FCSTUUFN. This NANU type is defined in the ICD, but not covered by the SOF definition in Appendix 3, so there is no ICD controlled way to add this outage type to the SOF.
The basics of how GPS works with some technical content.
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