they have the map, and you make a nav check to successfully plot a safe route, but you do not know the DC to avoid all dangers in the path. As we move through time frozen the only thing that has to be avoided is black holes everything else is harmless to pass by( basically gravity still reaches into time so you cant fly through a planet's core but can go through everything but the core. Stars and Black Holes have to be plotted around.
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they have the map, and you make a nav check to successfully plot a safe route, but you do not know the DC to avoid all dangers in the path. As we move through time frozen the only thing that has to be avoided is black holes everything else is not harmless to pass by( basically gravity still reaches into time so you can fly through a planet's core but can go through everything but the core. Stars and Black Holes have to be plotted around.