Editing Global Positioning System (section)

==Backup system==

In the event of adverse [[space weather]] or the deployment of an anti-satellite weapon against GPS, the United States has no terrestrial backup system. The potential cost of such an event to the U.S. economy is estimated at $1&nbsp;billion per day. The [[LORAN-C]] system was turned off in North America in 2010 and Europe in 2015. [[eLoran]] is proposed as an American terrestrial backup system, but as of 2024 has not received approval or funding.<ref>{{cite news |last1=Hegyi |first1=Nate |last2=Wong |first2=Wailin |date=September 27, 2024 |title=Losing GPS would cost the U.S. $1 billion a day. So why is there no backup? |url=https://www.npr.org/2024/09/27/nx-s1-5127737/losing-gps-would-cost-the-u-s-1-billion-a-day-so-why-is-there-no-backup |publisher=[[NPR]]}}</ref>

China continues to operate LORAN-C transmitters,<ref>{{cite web |author=Goward |first=Dana |date=November 15, 2019 |title=China leads world with plan for 'comprehensive' PNT |url=https://www.gpsworld.com/china-leads-world-with-plan-for-comprehensive-pnt/ |publisher=GPS World}}</ref> and Russia has a similar system called [[CHAYKA]] ("Seagull").