Perhaps the easiest thing to identify—and misuse—on every paper chart is the compass rose. It will typically display with an outer and inner ring. The outer ring will have a star at the top indicating ...

So, even if you’re standing in the Southern Hemisphere, your compass needle will always point north. Beyond the outer edges of the magnetosphere, however, things get a little more complicated.

And pushing a collision scenario further into the past, to hide this evidence, runs into the problem of the ages of stars: the outer ring of stars is quite blue in color, suggesting a younger age ...