GPS vs Celestial... new consideration

[N.A.]

Apparently there is now the possibility that GPS could be taken out not locally, but ocean-wide:

Tests suggest Russian satellites can jam GPS on a continental scale

Mystery of GPS interference across Europe raises questions about Russian motives.

arstechnica.com

Offshore I always carry a (plastic) sextant and the appropriate manuals, but... I don't really know how to use them. I think I might put a little more time into figuring that out before heading really far out.

Separately, I have become almost totally dependent on my chartplotter... not even bothering to log positions during day-trips. Even for local stuff outside the bay I think I will step up my log-keeping just so I can DR if need be / the fog comes in (as it can here.)

Everyone's risk profile will vary; mine was "I have 4 independent GPS sources on board, two of which have chart plotting... why do I need any further backup?" Considering current geopolitical uncertainties I think maybe a slight improvement in my backup plans wouldn't be a bad idea; I'll keep it simple though, since life is so much simpler just using the chartplotter : )

 

[Christian Williams]

Yes, GPS signal jamming or degrading is possible, and already apparent when sailing past bases near Point Conception, CA.

But wholesale degradation of GPS would disrupt or stop all civilian commerce, and is therefore a WW III scenario for which, it seems to me, a plastic sextant is not a likely solution. Nor is anything else.