Julien DeswaefAweigh is an open source navigation system that does not rely on satellites: it is inspired by the mapping of celestial bodies and the polarized vision of insects.
https://www.aweigh.io/
/cc: @neauoire @rek
#solarpunk
Matthew Skala@mattskala @neauoire @rek That's a very good question. I did not take this into account. I guess one of us will have to try.
Shekhinah@mattskala @xuv @neauoire @rek The SR-71 used to have navigation based on well-known stars, but the aweigh home page only says that it measures the sun's position. So that would be "celestial body" not "celestial bodies".
It also needs a real-time clock. I'm not sure if the SR-71's star tracker had that problem.
@CharredStencil @xuv @neauoire @rek A lot depends on the precision. If you need real time to one second, okay, no big deal although setting your clock accurately without using a reference that ultimately comes from GPS will be interesting. If you need microseconds, not so easy. Similarly, measuring the position of a star (including the Sun) to one degree is a lot easier than to one second of arc.
@CharredStencil @xuv @neauoire @rek Traditional celestial navigation (with a sextant and so on) can do star positions to one second of arc, which is what you need to even approach GPS, but only with expensive precision optics and a trained user. For doing it automatically, optical encoders good to that precision are *to this day* on the export-restricted-because-of-military-applications list, at least from Canada.