Satellite detections reach people through a distribution system, and that system has its own properties. NASA's Fire Information for Resource Management System publishes MODIS and VIIRS active-fire detections as downloadable points and map services, typically within about three hours of the satellite overpass and in some regions within about a minute through direct-readout ground stations. So a detection's age is the overpass gap plus the processing and delivery gap, and both belong in any statement about how quickly a fire was seen. The second property is that a thermal anomaly is not necessarily a wildfire. Gas flares at refineries and oil fields, steel works, volcanic activity, sun glint off water and bright bare soil all produce persistent or recurring detections, which is why an operational user filters against known static heat sources and treats a lone low-confidence detection as a question rather than an answer. After this Concept you can state the true age of a hot-spot detection and name the non-fire sources that will appear in the same feed.
Satellite-derived active fire detection represents each fire as a discrete point (a "hotspot") located somewhere within a sensor's spatial resolution cell (pixel), so a detection indicates that therm…