Home›Maneuver Tracker›Close Approaches›COSMOS 2184 ⟷ SL-8 R/B
HighProximity
RussiaCOSMOS 2184NORAD 21937 · launched Apr 1992Military payload
2.88kmPredicted miss distance
RussiaSL-8 R/BNORAD 15506 · launched Feb 1985Rocket body
ForecastForecast made 10 Nov 09:38 UTC.
Closest approach10 Nov 202618:03 UTC
Relative speed11.42 km/sat the closest approach
Altitude958 kmlow Earth orbit
Last confirmed10 Nov09:38 UTC · forecast
Track COSMOS 2184Track SL-8 R/BAll approaches
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RU COSMOS 2184 and RU SL-8 R/B are predicted to reach a closest approach of 2.88 km at 2026-11-10 18:03 UTC, at a relative speed of 11.42 km/s. Forecast made 10 Nov 09:38 UTC. 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 2184Payload
NORAD 21937
CountryCIS
Launched1992-04-15
OrbitLEO · 962 × 1,013 km
COSPAR1992-020A
Maneuver capableUnknown
Profile →Globe →
SL-8 R/BR/B
NORAD 15506
CountryCIS
Launched1985-02-01
OrbitLEO · 949 × 1,003 km
COSPAR1985-011B
Maneuver capableNo
Spent rocket stage: uncontrolled, tracked by the public catalogue.
Profile →Globe →

Where This Happens

Altitude context
DEBRIS BELT 700–1000 KM2006001,0001,5002,000 kmTHIS PASS · 958 KMISS 420Starlink 550

At 958 km this pass sits inside the most congested band in low Earth orbit, home to the debris left by the 2007 ASAT test and the 2009 collision. 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 2184 ⟷ SL-8 R/B
2026-11-10 18:032.88 km Forecast11.42 km/s958 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
10 Nov 09:32 UTC2.88 km Forecast10 Nov 18:03 UTC9 Nov 17:23 UTCRe-check
9 Nov 21:51 UTC2.88 km Forecast10 Nov 18:03 UTC9 Nov 14:29 UTCRe-check
9 Nov 21:33 UTC6.28 km Forecast10 Nov 18:03 UTC9 Nov 05:35 UTCScreen

These Objects Elsewhere

Other screened approaches · 7 days
533 m11-07 01:26 UTC
COSMOS 2184COSMOS 1275 DEB
933 m11-11 05:36 UTC
COSMOS 2184FENGYUN 1C DEB
2.08 km11-10 10:13 UTC
COSMOS 2184COSMOS 1275 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 →