Distance and latitude/longitude coordinates are displayed when you mouse over the map. The origin for distance measuring is indicated by a red dot and defaults to either your location, if specified and in range, or the location of the radar/the centre of the map. The origin may be changed by clicking elsewhere on the map.
14:22 AEST Alice Springs sits at the centre. Geographically, the town is roughly 1500 km equidistant from both Darwin and Adelaide. Culturally, it demarcates 'up north' from 'down south'. And meteorologically, at 23 degrees latitude, it separates the tropics from the mid-latitudes, marking the general limit for the reach of southern cold-fronts.