The Constellation Status tool presents a view of the GPS satellite constellation based on the latest almanac and NANUs (Notice Advisory to Navigation Users) issued by the US Coast Guard.
The Constellation Status tool presents the number of operational satellites in the GPS constellation based on the information current at the time of viewing. The almanac used and NANUs that affect the availability of satellites during the requested time period are also displayed.
The Constellation Status tool is configured to provide the status of the GPS constellation for a 72 hour period calculated from the midnight previous to the time at which the status request was made (times are in UTC).