Home›Maneuver Tracker›Close Approaches›TIANLIAN-3 01 ⟷ RADUGA 28
HighCross-border
On permanent record
Live forecastConfirmed by the latest screening, 30 Oct 17:33 UTC.
Closest approach31 Oct 202613:42 UTC
Drift speed710 m/s2,555 km/h, seen from RADUGA 28
Altitude35,780 kmnear the geostationary belt
Separation now—live

CN TIANLIAN-3 01 and RU RADUGA 28 are predicted to reach a closest approach of 2.71 km at 2026-10-31 13:42 UTC, drifting past at about 710 m/s (2,555 km/h) as seen from RADUGA 28. Confirmed by the latest screening, 30 Oct 17:33 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
NORAD 100172
CountryPRC
Launched2026-07-29
COSPAR2026-172A
Maneuver capableUnknown
RADUGA 28Payload
NORAD 21821
CountryCIS
Launched1991-12-19
COSPAR1991-087A
Maneuver capableUnknown

Where This Happens

Altitude context
GEO BELT 35,786 KMTHIS PASS · 35,780 KMLEOMEOGEO

This pass happens near the geostationary belt, where satellites hold fixed longitude slots and relative speeds are low. Close approaches here are usually slow drifts rather than crossing passes. About GEO →

History Between This Pair

1 predicted pass under 10 km
Pair history · TIANLIAN-3 01 ⟷ RADUGA 28
2026-10-31 13:422.71 km Live forecast0.71 km/s35,780 kmShown above

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 Nothing is overwritten: a withdrawn forecast keeps its figure, with the newer check beside it, and the best estimate after the pass is a row of its own.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
30 Oct 13:52 UTC2.72 km Forecast31 Oct 13:42 UTC29 Oct 22:12 UTCScreen

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 →

Cite this encounter: Orbital Radar — “TIANLIAN-3 01 ⟷ RADUGA 28: 2.71 km predicted close approach”, https://orbitalradar.com/conjunction/100172-21821 (accessed 2026-10-30).
✓ Permanent record. This encounter met the notability thresholds and keeps an archived page after the pass.