Home›Maneuver Tracker›Close Approaches›COSMOS 2354 ⟷ SL-8 DEB
MediumProximity
RussiaCOSMOS 2354NORAD 25365 · launched Jun 1998Military payload
7.39kmPredicted miss distance
RussiaSL-8 DEBNORAD 21176 · launched Feb 1991Debris
Final forecastFinal forecast, made 17 min before the pass.
Closest approach28 Oct 202615:32 UTC
Relative speed13.60 km/sat the closest approach
Altitude1,723 kmlow Earth orbit
Last confirmed28 Oct15:15 UTC · final forecast
Track COSMOS 2354Track SL-8 DEBAll approaches
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RU COSMOS 2354 and RU SL-8 DEB were predicted to reach a closest approach of 7.39 km at 2026-10-28 15:32 UTC, at a relative speed of 13.60 km/s. Final forecast, made 17 min before the pass. 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 mattersOne side of this pass cannot maneuver, so any avoidance decision rests with the other operator. Screening continues as new element sets arrive.

The Two Objects

Dossiers from the satellite directory
COSMOS 2354Payload
NORAD 25365
CountryCIS
Launched1998-06-15
OrbitLEO · 1,308 × 1,870 km
COSPAR1998-036C
Maneuver capableUnknown
Profile →Globe →
SL-8 DEBDebris
NORAD 21176
CountryCIS
Launched1991-02-12
OrbitLEO · 1,437 × 1,765 km
COSPAR1991-009AP
Maneuver capableNo
Uncontrolled debris fragment tracked by the public catalogue. About space debris →
Profile →Globe →

Where This Happens

Altitude context
DEBRIS BELT 700–1000 KM2006001,0001,5002,000 kmTHIS PASS · 1723 KMISS 420Starlink 550

At 1723 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

1 predicted pass under 10 km
Pair history · COSMOS 2354 ⟷ SL-8 DEB
2026-10-28 15:327.39 km Final forecast13.60 km/s1,723 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 Nothing is overwritten: a withdrawn forecast keeps its figure, with the newer check beside it, and the best estimate after the pass is a row of its own.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
28 Oct 12:15 UTC7.39 km Forecast28 Oct 15:32 UTC27 Oct 22:59 UTCRe-check
28 Oct 11:56 UTC8.99 km Forecast28 Oct 15:32 UTC27 Oct 22:59 UTCScreen

These Objects Elsewhere

Other screened approaches · 7 days
6.06 km10-31 20:33 UTC
COSMOS 2354COSMOS 506
7.46 km11-01 00:32 UTC
COSMOS 2159COSMOS 2354
8.08 km10-27 18:14 UTC
COSMOS 2354DELTA 1 DEB

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 — “COSMOS 2354 ⟷ SL-8 DEB: 7.39 km predicted close approach”, https://orbitalradar.com/conjunction/21176-25365 (accessed 2026-11-01).