CN YAOGAN-35 05A and US FLOCK 4H-14 were predicted to reach a closest approach of 9.95 km at 2026-10-27 08:48 UTC, at a relative speed of 13.50 km/s. Last re-confirmed by the screening 5 h before the pass. Newer orbit data, from 27 Oct 00:45 UTC, put them 10.1 km apart. Best estimate after the pass, from the orbit data published nearest its time: 8.65 km at 27 Oct 08:48 UTC. This is a cross-border encounter between objects of different nations, the kind of event closely watched for space-security implications. Miss distance and time of closest approach are computed by propagating the latest published orbital elements for both objects, and each pass is re-checked every 20 minutes as new element sets are published. See the Satellite Maneuver Tracker for the live picture and space situational awareness for context.

The Two Objects

Where This Happens

History Between This Pair

Repeat encounters are common for objects in near-intersecting orbital planes. Each pass is re-screened as fresh element sets arrive; "Final forecast" means the screening still predicted it within 45 minutes of its time, "Not re-confirmed" means later screening stopped finding it.

Forecast Record

These Objects Elsewhere

How These Numbers Are Computed

Miss distance and TCA come from propagating the latest published orbital elements for both objects and searching for the minimum separation over the screening window. Element sets carry kilometre-scale uncertainty, so figures here describe a close pass, not a collision prediction; a change in either object's published elements re-computes the pass automatically. What is a conjunction? → How conjunction assessment works →