As the clock hits 23:59:59 UTC tonight on April 6, something peculiar is happening around the globe and literally in the space. Global Position System (GPS) is a constellation of 31 active satellites at the moment that operates by broadcasting signals onto the Earth that receivers catch up that allows the satellites to determine their speed, distance, and time while contemplating user’s location on the Earth. However, tonight, the GPS is undergoing zero days when it will flip back 19.7 years that mustn’t hit any newer GPS systems although older systems that haven’t made any accommodation to facilitate the rollover might suffer.
To shed light on what’s happening, tonight, the satellite navigation system that users 10-bit week number (WN) counter will hit its epitome before flipping back to 0000000000. This is considered as GPS epoch or rollover or zero-day and the last epoch was reported on August 21, 1999.
According to Ars Technica, the Department of Homeland Security’s National Cybersecurity & Communications Integration Center issues warning back in April 2018 about the upcoming epoch that hits GPS navigation systems every 1,024 weeks which is around 19.7 years. The zero-day will hit older GPS systems that are made up with 10 bits WN. Fast forward to the coming future, modernization of GPS constellation consisting of more than 30 satellites is taking place and once it is done, the WN counter will be escalated to carry 13 bits of weeks that would delay the epoch.
Based on a report published by Ars Technica, this rollover that commences precisely at 23:59:59 UTC tonight on April 06 will not affect location calculations, however, there will be a jump of 19.7 years where the WN counter will be reset to 0000000000. This wouldn’t affect much of the systems, although GPS receivers that aren’t able to cope up with the rollover might observe time lags that will affect navigational data in other ways possible,
Moreover, the rollover could affect electrical utilities, cellular networks, and so on since these systems are made to withstand a longer lifecycle and thus, aren’t updated as much which might cause a problem as said.
There is a possibility that the GPS apps we use on mobile phones or computers could go haywire tomorrow i.e. on Sunday morning, however, this isn’t a chance for the firmware that is updated and knows how to cope up with rollover. The next GPS epoch is estimated to occur sometime in 2039 if the GPS constellations are still using 10 bits WN counter, however, since we already know that competent authorities are updating satellites to form a new constellation, this wouldn’t be a case.