Revisit time is how long a satellite system takes to observe the same location again — from weeks for a single high-resolution imager to under an hour for large constellations. It defines what changes a system can catch, and it is bought with satellites.
Understanding Revisit Time
The constellation arithmetic
Distribute N satellites across complementary planes and revisit divides by roughly N — the scaling that turned Earth observation into a fleet business. Design finesse lies in phasing: spreading local crossing times to sample different hours (morning agriculture light, afternoon storm development), mixing sensor classes so high-resolution assets are cued by wide-swath scouts, and accepting heterogeneous fleets where yesterday's satellites thicken today's coverage.
Revisit as intelligence tempo
The metric's sharpest consumers measure change: port activity between mornings, vehicles between hours, damage between orbits. Sub-daily revisit converted satellite imagery from archival record to operational feed — wildfire perimeters updated through the day, ships tracked between AIS gaps, humanitarian response mapped while events unfold. Every step down in revisit time opens a class of questions that stale imagery simply cannot answer.