explainer
3 articlesNight Lights, SO2, Earthquakes and Cyclones: Four Measured Events and What Each One Can and Cannot Tell You
Four kinds of event built from instruments and official records instead of news: a city's night lights, sulfur dioxide over a volcano, an earthquake near a facility, and a cyclone's forecast wind field. What each records, and what it leaves open.
2026-10-08 · 9 min read
What Is a Transit Anomaly? Telling an Unusual Change in Ship Traffic at a Strait from Routine Variation
A transit anomaly is a count of ships through a strait or canal that has left that place's own usual level. How transits are counted from AIS, what moves the count besides a disruption, and how to read it without guessing a cause.
2026-10-07 · 11 min read
What Is a Thermal Anomaly? Telling an Unusual Heat Source from a Routine Flare in Satellite Data
A thermal anomaly is a satellite pixel flagged as hot. At a refinery or power plant most of them are routine. How NASA separates static heat sources, and how to compare a heat source with its own past.
2026-10-06 · 10 min read