Abstract: A system for enhancing navigation or surveillance in low visibility conditions is realized by employing one or more ultraviolet radiation sources, a receiver which is capable of producing output signals from which a two dimensional image of the received radiation can be constructed, and a display device for displaying such image. In one preferred embodiment the ultraviolet radiation source is co-positioned with a critical marker such as a runway beacon or hazard beacon. The ultraviolet radiation emanates from the source, preferably modulated to form a repetitive, characteristic signal, propagates through the low visibility atmosphere, and received by the ultraviolet imaging receiver. In another preferred embodiment, an ultraviolet radiation source is placed at or near the ultraviolet imaging receiver, that is, onboard the same vehicle or at the same fixed location. One or more reflectors are co-positioned with the critical markers.