Horrors! This site has a much, much greater "discontinuity."
http://www.isstracker.com/Actually, it's one of the best maps for the ISS's orbits on the internet, because you can change so many things on it. Select three different maps, remove the ISS's ground track (and that "discontinuity"), uncentre the ISS, remove or show its horizon, change to metric units (yay!), and zoom in and out to a large degree.
The horizon is useful for three things -- it shows what's visible from the ISS, the areas on the ground from where it can be seen, and it lightens the night-time view of the ground around the ISS.
Uncentering the ISS is useful for zooming in on a particular part of any ground track, such as seeing how close it will pass to your particular location on the current orbit or the next two.
