Home›Maneuver Tracker›Close Approaches›COSMOS 2128 ⟷ DELTA 1 DEB
HighCross-border
RussiaCOSMOS 2128NORAD 21103 · launched Feb 1991Military payload
5.80kmPredicted miss distance
United StatesDELTA 1 DEBNORAD 18906 · launched Nov 1973Debris
Final forecastFinal forecast, made 12 min before the pass.
After the passBest estimate, from the orbit data published nearest its time: 5.84 km at 7 Nov 14:03 UTC.
Closest approach7 Nov 202614:03 UTC
Relative speed12.91 km/sat the closest approach
Altitude1,457 kmlow Earth orbit
Last confirmed7 Nov13:51 UTC · final forecast
Track COSMOS 2128Track DELTA 1 DEBAll approaches
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RU COSMOS 2128 and US DELTA 1 DEB were predicted to reach a closest approach of 5.80 km at 2026-11-07 14:03 UTC, at a relative speed of 12.91 km/s. Final forecast, made 12 min before the pass. Best estimate after the pass, from the orbit data published nearest its time: 5.84 km at 7 Nov 14:03 UTC. This is a cross-border encounter between objects of different nations. 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 2128Payload
NORAD 21103
CountryCIS
Launched1991-02-12
OrbitLEO · 1,445 × 1,468 km
COSPAR1991-009D
Maneuver capableUnknown
Profile →Globe →
DELTA 1 DEBDebris
NORAD 18906
CountryUS
Launched1973-11-06
OrbitLEO · 1,370 × 1,509 km
COSPAR1973-086HB
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 · 1457 KMISS 420Starlink 550

At 1457 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 2128 ⟷ DELTA 1 DEB
2026-11-07 14:035.80 km Final forecast · after: 5.84 km12.91 km/s1,457 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
11 Nov 20:17 UTC5.84 km Best estimate7 Nov 14:03 UTC7 Nov 19:20 UTCBest estimate
7 Nov 12:51 UTC5.80 km Forecast7 Nov 14:03 UTC7 Nov 07:50 UTCRe-check
7 Nov 09:18 UTC5.78 km Forecast7 Nov 14:03 UTC6 Nov 22:24 UTCRe-check
6 Nov 22:14 UTC5.90 km Forecast7 Nov 14:03 UTC6 Nov 14:50 UTCRe-check
6 Nov 20:34 UTC5.72 km Forecast7 Nov 14:03 UTC5 Nov 19:24 UTCRe-check
6 Nov 20:31 UTC7.95 km Forecast7 Nov 14:03 UTC5 Nov 19:24 UTCScreen

These Objects Elsewhere

Other screened approaches · 7 days
3.19 km11-07 08:19 UTC
COSMOS 2071DELTA 1 DEB
3.26 km11-12 11:45 UTC
COSMOS 2069DELTA 1 DEB
3.71 km11-06 19:58 UTC
COSMOS 2128COSMOS 1823 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 →