[tomalpha]

It does, perhaps, have the advantage of not needed a satellite fleet to work. So therefore isn’t at the whim of said fleet’s owner, or someone with anti-satellite missiles.

(Granted that the antenna size problem might be a killer)

[gambiting]

Star trackers do exactly this, providing relatively accurate positioning without GPS:

https://en.wikipedia.org/wiki/Star_tracker

[MayeulC]

I was about to suggest the use of a sextant for this. As far as I know, navigators are still trained to operate them in this day. Of course, the same operational principle can be integrated into a dedicated device.

[oceanswave]

Was going to say this, and in use by things like submarines and ships since the 60’s