GPS satellite outages are determined by the US Air 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.
As of 2017-07-21 22:32:27Z
GPS satellite outages identified as current by the US Air 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 Air Force.
There are no predicted outages at this time.
GPS satellite outages identified as historical by the US Air Force, occurring within the last month.
|PRN||SVN||NANU||Type||Outage start||Outage stop||Duration|
|13||43||2017058||FCSTSUMM||Jun 22, 2017||Jun 22, 2017||00d:02h:35m:000s|
|16||56||2017061||FCSTSUMM||Jun 27, 2017||Jun 27, 2017||00d:02h:58m:000s|
|20||51||2017063||FCSTSUMM||Jun 29, 2017||Jun 30, 2017||00d:02h:32m:000s|
|2||61||2017066||FCSTSUMM||Jul 06, 2017||Jul 07, 2017||00d:05h:28m:000s|
|23||60||2017067||FCSTSUMM||Jul 11, 2017||Jul 12, 2017||00d:02h:35m:000s|
|5||50||2017069||FCSTSUMM||Jul 13, 2017||Jul 14, 2017||00d:02h:44m:000s|
|7||48||2017071||FCSTSUMM||Jul 18, 2017||Jul 19, 2017||00d:06h:00m:000s|
GPS outages in a calendar format from AGI can be found here:
Historical GPS Outages can be found here:
The basics of how GPS works with some technical content.
How Long Can You Use an Almanac?
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Operational Considerations for Improved Accuracy with an IOC Galileo Constellation
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