1. In a computerized system including a camera mounted on a moving vehicle, a maneuverless, passive method for determining a range of a foreign moving object from said moving vehicle, wherein said foreign moving object is not part of said computerized system, the method comprising the steps of: acquiring with said camera, consecutively in real time, a plurality of images of said foreign moving object wherein no positional data is received from said foreign moving object; detecting said foreign moving object within each of said plurality of images; identifying two feature points p 1 and p 2 on said detected object within each of said plurality images, where p 1 and p 2 are utilized to determine a direction of travel of said detected object and where p 1 and p 2 satisfy a predetermined geometric relationship with a velocity vector of said detected object; and recursively calculating the range of said detected object based on changes in the positions of the feature points p 1 and p 2 in the sequential images and further based on said predetermined geometric relationship without any positional data being received from said detected object and without any assumptions of position or movement of the detected object based on background references.