Strait of Hormuz — AIS monitor

These are samples, not tracks. The collector opens the AIS stream for 180 seconds about every 15 minutes; the gaps between windows are not observed, and shore-based receivers do not cover the middle of the strait. An absent vessel is unknown, not absent. How this is collected

Radar circles are not ships: they are bright objects the size of a vessel in one Sentinel-1 image. A pass comes about once every two days and is one instant, not a track. Within 1 km of the shore, terrain laid over by the radar is mixed with real hulls, so that band is off by default, and so are the weak detections further out, most of which the radar's second channel does not confirm. Some of the strong ones out at sea recur in the same place pass after pass: anchorages, platforms, or artefacts of the radar's viewing angle. A pass sees only part of the box; where it did not look is unobserved, not empty. None of them is matched to an AIS identity.