A system for searching for a thermal target, comprising: a wide field-of-view thermal imager disposed on an aerial or a moving platform and configured for directing toward a search area and registering thermal signals across a field of view of the wide field-of-view thermal imager; characterised in that the system further comprises: a global navigation satellite system receiver and an inertial navigation system disposed on the aerial or moving platform and coupled to the wide field-of-view thermal imager; a narrow field-of-view thermal-imaging video imager configured to point and zoom to a field of view that is less than or equal to 10% of the wide field-of-view; and a computer connected to the wide field-of-view thermal imager, the narrow field-of-view thermal imager the global navigation satellite system receiver and the inertial navigation system, wherein the computer is configured to time-integrate the amplitude of the thermal signals emanating from each sector in the search area imaged by the wide field-of-view thermal imager, identify one or more sectors of interest having an average thermal signal that is at least three standard deviations above a local mean thermal signal, determine the GPS position of the one or more sectors of interest by combining navigation and orientation data from the global navigation satellite system receiver and the inertial navigation system with known geometric data about the field-of-view of the wide field-of-view imager and direct the narrow field-of-view thermal imager to point to the GPS position of the sector of interest and display a thermal image associated with the sector of interest to a user. a wide field-of-view thermal imager disposed on an aerial or a moving platform and configured for directing toward a search area and registering thermal signals across a field of view of the wide field-of-view thermal imager; characterised in that the system further comprises: a global navigation satellite system receiver and an inertial navigation system disposed on the aerial or moving platform and coupled to the wide field-of-view thermal imager; a narrow field-of-view thermal-imaging video imager configured to point and zoom to a field of view that is less than or equal to 10% of the wide field-of-view; and a computer connected to the wide field-of-view thermal imager, the narrow field-of-view thermal imager the global navigation satellite system receiver and the inertial navigation system, wherein the computer is configured to time-integrate the amplitude of the thermal signals emanating from each sector in the search area imaged by the wide field-of-view thermal imager, identify one or more sectors of interest having an average thermal signal that is at least three standard deviations above a local mean thermal signal, determine the GPS position of the one or more sectors of interest by combining navigation and orientation data from the global navigation satellite system receiver and the inertial navigation system with known geometric data about the field-of-view of the wide field-of-view imager and direct the narrow field-of-view thermal imager to point to the GPS position of the sector of interest and display a thermal image associated with the sector of interest to a user. a global navigation satellite system receiver and an inertial navigation system disposed on the aerial or moving platform and coupled to the wide field-of-view thermal imager; a narrow field-of-view thermal-imaging video imager configured to point and zoom to a field of view that is less than or equal to 10% of the wide field-of-view; and a computer connected to the wide field-of-view thermal imager, the narrow field-of-view thermal imager the global navigation satellite system receiver and the inertial navigation system, wherein the computer is configured to time-integrate the amplitude of the thermal signals emanating from each sector in the search area imaged by the wide field-of-view thermal imager, identify one or more sectors of interest having an average thermal signal that is at least three standard deviations above a local mean thermal signal, determine the GPS position of the one or more sectors of interest by combining navigation and orientation data from the global navigation satellite system receiver and the inertial navigation system with known geometric data about the field-of-view of the wide field-of-view imager and direct the narrow field-of-view thermal imager to point to the GPS position of the sector of interest and display a thermal image associated with the sector of interest to a user.