You don’t need to see the horizon at all, you just need to establish a vector that points Up. Traditional instruments used the horizon, but now we have gyroscop

You don’t need to see the horizon at all, you just need to establish a vector that points Up. Traditional instruments used the horizon, but now we have gyroscopes, gravity sensors and satellite surveys of the Earth’s density and magnetic field, none of which require GPS or networking. You don’t need a wide field of view either, you just need an enough pairs of stars that the plate solver can provide an accurate reading of what in the celestial sphere the camera is actually looking at.