The blue arrow marker is displayed next to the location you are nearest to in the list. An orange arrow marker is displayed next to the location you have locked into your ship's navigation targeting computer.
This. If you leave that panel open and watch it, you'll see the blue marker switch around to different bodies as you move through the system.
Unless of course you crash into something on account of not watching where you're supercruising.
Azeban orbital. My very favorite place to sit with a rift on. That tight orbit looks spectacular.