Home›Maneuver Tracker›Close Approaches›YAOGAN 21 ⟷ STARLINK-31683
HighCross-border
Live forecastConfirmed by the latest screening, 4 Nov 22:52 UTC.
Closest approach5 Nov 202607:46 UTC
Relative speed12.21 km/sat the closest approach
Altitude480 kmlow Earth orbit
Separation now—live

CN YAOGAN 21 and US STARLINK-31683 are predicted to reach a closest approach of 7.35 km at 2026-11-05 07:46 UTC, at a relative speed of 12.21 km/s. Confirmed by the latest screening, 4 Nov 22:52 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.

Why it mattersBoth objects are catalogued as payloads. Screening continues as new element sets arrive; operators act on their own conjunction data.

The Two Objects

Dossiers from the satellite directory
YAOGAN 21Payload
NORAD 40143
CountryPRC
Launched2014-09-08
COSPAR2014-053A
Maneuver capableUnknown
NORAD 59573
CountryUS
Launched2024-04-23
COSPAR2024-076K
Maneuver capableUnknown

Where This Happens

Altitude context
DEBRIS BELT 700–1000 KM2006001,0001,5002,000 kmTHIS PASS · 480 KMISS 420Starlink 550

At 480 km this pass sits in low Earth orbit. Objects here stay up for decades: there is too little atmospheric drag to clean the band naturally. Why crowded bands matter →

History Between This Pair

3 predicted passes under 10 km
Pair history · YAOGAN 21 ⟷ STARLINK-31683
2026-11-05 07:467.35 km Live forecast12.21 km/s480 kmShown above
2026-11-05 05:243.38 km Live forecast12.23 km/s485 kmView →
2026-10-28 15:577.15 km Final forecast14.11 km/s484 kmView →

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

Every figure published for the pass shown above, newest first. Nothing is overwritten: a withdrawn forecast keeps its figure, with the newer check beside it, and the best estimate after the pass is a row of its own.
Computed · figure · predicted time · orbit data · by
4 Nov 21:11 UTC7.35 km Forecast5 Nov 07:46 UTC4 Nov 16:23 UTCRe-check
4 Nov 18:18 UTC7.11 km Forecast5 Nov 07:46 UTC4 Nov 13:47 UTCRe-check
4 Nov 17:58 UTC8.01 km Forecast5 Nov 07:46 UTC4 Nov 13:47 UTCScreen

These Objects Elsewhere

Other screened approaches · 7 days
1.06 km11-02 14:54 UTC
YAOGAN 21STARLINK-33972
1.39 km11-04 06:10 UTC
YAOGAN 21STARLINK-31908
1.41 km11-04 18:46 UTC
YAOGAN 21STARLINK-36607

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 →