From ASSS Wiki
Pixels are the smallest units of measurement in Continuum. Although they can't transform directly with a real life measurement (you can't go from pixels to meters, for example), they are used heavily in Continuum. Each tile in a map contains 16 pixels across and 16 pixels down. When players move around, their position can lie on any one of these pixels. This means that if you say "Player X is at (512, 512)" He could actually be in one of 256 different locations (16 * 16 = 256). A ship's radius is also measured in pixels. Speeds are also measured using pixels, typically in pixels / 10 seconds.