1. A sensor system for tracking and navigation, comprising: two sensors, each sensor comprising a two-dimensional plurality of discrete detection pixels; for each said sensor, computerized data associating each said detection pixel thereof with a predetermined azimuth angle and a predetermined elevation angle; a computerized device for automatically determining azimuth angles and elevation angles of electro-magnetic radiation from a target or beacon simultaneously detected by each of said sensors, for each of said sensors, based on said computerized data; and said sensor system omitting means for focusing a spot of electro-magnetic radiation onto said target or beacon to be so-detected.