HomeManeuver TrackerClose ApproachesCOSMOS 1320 ⟷ SL-8 DEB
medium · PROXIMITY
6.84 kmmiss distance
Closest approach (TCA)
2026-09-15 20:15 UTC
Relative speed
7.17 km/s
Altitude
Current separation
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On 2026-09-15 20:15 UTC, RU COSMOS 1320 and RU SL-8 DEB reached a closest approach (TCA) of 6.84 km, with a relative velocity of 7.17 km/s. Miss distance and time of closest approach are computed by propagating the latest published orbital elements for both objects, and values update 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
NORAD 12975
CountryCIS
Launched1981-11-28
COSPAR1981-116A
Maneuver capableUnknown
SL-8 DEBDebris
NORAD 39839
CountryCIS
Launched1991-02-12
COSPAR1991-009DX
Maneuver capableNo
Uncontrolled debris fragment tracked by the public catalogue. About space debris →

Where This Happens

Altitude context
DEBRIS BELT 700–1000 KM2006001,0001,5002,000 kmTHIS PASS · 1495 KMISS 420Starlink 550

At 1495 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 recorded pass under 10 km
Pair history · COSMOS 1320 ⟷ SL-8 DEB
Now6.84 km7.17 km/s1,495 kmThis page

Repeat encounters are common for objects in near-intersecting orbital planes; each pass is re-screened as fresh element sets arrive.

These Objects Elsewhere

Other screened approaches · 7 days
3.59 km09-15 22:07 UTC
COSMOS 1040COSMOS 1320
4.09 km09-09 22:33 UTC
COSMOS 1320DELTA 1 DEB
5.62 km09-10 17:19 UTC
COSMOS 1823 DEBSL-8 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 1320 ⟷ SL-8 DEB: 6.84 km close approach”, https://orbitalradar.com/conjunction/12975-39839 (accessed 2026-09-15).