|Just after sunrise, clouds cast shadows onto the North Atlantic.|
"A great circle route is the shortest path between two points on a sphere — imagine extending a string between two cities on a desktop globe. In the northern hemisphere, these routes, modified by the wind and other considerations, often take us far closer to the North Pole than most of us are likely to otherwise go (here's a fun great circle mapping tool to play with).".More here
Vanhoenacker has also written a book called Skyfaring.