Home›Maneuver Tracker›Close Approaches›COSMOS 2126 ⟷ COSMOS 1823 DEB
MediumProximity
RussiaCOSMOS 2126NORAD 21101 · launched Feb 1991Military payload
5.66kmPredicted miss distance
RussiaCOSMOS 1823 DEBNORAD 18727 · launched Feb 1987Military debris
Final forecastFinal forecast, made 18 min before the pass.
Closest approach27 Oct 202603:41 UTC
Relative speed9.29 km/sat the closest approach
Altitude1,475 kmlow Earth orbit
Last confirmed27 Oct03:24 UTC · final forecast
Track COSMOS 2126Track COSMOS 1823 DEBAll approaches
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RU COSMOS 2126 and RU COSMOS 1823 DEB were predicted to reach a closest approach of 5.66 km at 2026-10-27 03:41 UTC, at a relative speed of 9.29 km/s. Final forecast, made 18 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 2126Payload
NORAD 21101
CountryCIS
Launched1991-02-12
OrbitLEO · 1,466 × 1,496 km
COSPAR1991-009B
Maneuver capableUnknown
Profile →Globe →
COSMOS 1823 DEBDebris
NORAD 18727
CountryCIS
Launched1987-02-20
OrbitLEO · 1,333 × 1,470 km
COSPAR1987-020E
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 · 1475 KMISS 420Starlink 550

At 1475 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 2126 ⟷ COSMOS 1823 DEB
2026-10-27 03:415.66 km Final forecast9.29 km/s1,475 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
26 Oct 16:41 UTC5.66 km Forecast27 Oct 03:41 UTC26 Oct 07:04 UTCRe-check
26 Oct 10:06 UTC5.61 km Forecast27 Oct 03:41 UTC25 Oct 23:42 UTCRe-check
26 Oct 09:48 UTC6.18 km Forecast27 Oct 03:41 UTC25 Oct 23:42 UTCScreen

These Objects Elsewhere

Other screened approaches · 7 days
681 m10-26 09:50 UTC
COSMOS 2126DELTA 1 DEB
4.86 km10-31 10:45 UTC
COSMOS 2126COSMOS 1803
6.07 km10-25 12:33 UTC
COSMOS 2126COSMOS 793

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 2126 ⟷ COSMOS 1823 DEB: 5.66 km predicted close approach”, https://orbitalradar.com/conjunction/18727-21101 (accessed 2026-10-30).