All information on this page is taken from the GPS Satellite Outage File and SEM almanacs produced by the US Air Force 2nd Space Operations Squadron, and made available by the US Coast Guard.

Satellite Outage File (SOF) Details

The current SOF is available from CelesTrak here:	2021_245_180323_v01.sof
The latest check for a SOF was on:	2021 September 17, 19:21:59
The SOF was last retrieved on:	2021 September 17, 17:20:17

GPS Satellite Outage Calendar

Historical outages are colored black, Predicted outages are colored gold, Current outages are colored red

January February March April May June July August September October November December   1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021    

August September 2021 October
Su	Mo	Tu	We	Th	Fr	Sa
			1 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	2 PRN 27 B 10:47 E 18:02 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	3 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	4 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11
5 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	6 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	7 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	8 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	9 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	10 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	11 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11
12 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	13 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	14 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	15 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	16 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	17 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	18 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11
19 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	20 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	21 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	22 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	23 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	24 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	25 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11
26 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	27 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	28 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	29 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11	30 PRN 18 PRN 23 PRN 14 PRN 11 PRN 28 PRN 11

Current GPS Outages

Current Outages

Predicted GPS Outages

Predicted Outages

Historical GPS Outages

A GPS historical outage table can be accessed from the link below. The historical outages table contains all GPS outages since 1998.

Historical Outages

GPS Satellite Health Information

The information below shows the number of healthy GPS satellites, since 1998. The number of satellites in the GPS constellation comes from the SEM almanac for that day. The number of unhealthy satellites for that day comes from the Satellite Outage File. The SOF outages are subtracted from the number of satellites in the constellation to get the number of healthy satellites.

The list of unused PRN numbers come from those PRNs not listed in the SEM almanac.

Number of GPS satellites in the latest almanac:	31
Number of unhealthy GPS satellites in the SOF:	6
Current number of healthy GPS satellites:	25
Unused PRN number(s):	28

Healthy GPS Satellites Graph

This graph plots the number of healthy GPS satellites since 1998 (Full History), or over the last 365 days.

Note that since this is calculated on a daily boundary, this graph will show sequential outages in a single day as concurrent, and may not reflect the more updated statistics above.

Full HistoryLast 365 Days