Home›Maneuver Tracker›Close Approaches›REASON-1 ⟷ OBJECT CK
HighProximity
Final forecastFinal forecast, made 11 min before the pass.
Closest approach7 Nov 202617:23 UTC
Drift speed3.0 m/s11 km/h, seen from OBJECT CK
Altitude522 kmlow Earth orbit
Last confirmed7 Nov17:11 UTC · final forecast

US REASON-1 and TBD OBJECT CK were predicted to reach a closest approach of 2.34 km at 2026-11-07 17:23 UTC, drifting past at about 3.0 m/s (11 km/h) as seen from OBJECT CK. Final forecast, made 11 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 mattersBoth objects are catalogued as payloads. Screening continues as new element sets arrive; operators act on their own conjunction data.

The Two Objects

Dossiers from the satellite directory
REASON-1Payload
NORAD 100903
CountryUS
Launched2026-10-01
COSPAR2026-227W
Maneuver capableUnknown
OBJECT CKPayload
NORAD 101097
CountryTBD
Launched2026-10-01
COSPAR2026-227CK
Maneuver capableUnknown

Where This Happens

Altitude context
DEBRIS BELT 700–1000 KM2006001,0001,5002,000 kmTHIS PASS · 522 KMISS 420Starlink 550

At 522 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

2 predicted passes under 10 km
Pair history · REASON-1 ⟷ OBJECT CK
2026-11-07 17:232.34 km Final forecast0.01 km/s522 kmShown above
2026-11-07 15:09927 m Final forecast0.00 km/s505 kmView →

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 Nothing is overwritten: a withdrawn forecast keeps its figure, with the newer check beside it, and the best estimate after the pass is a row of its own.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
7 Nov 12:51 UTC2.34 km Forecast7 Nov 17:23 UTC7 Nov 03:40 UTCRe-check
7 Nov 09:18 UTC1.62 km Forecast7 Nov 17:17 UTC6 Nov 22:55 UTCRe-check
6 Nov 22:14 UTC701 m Forecast7 Nov 17:23 UTC6 Nov 03:56 UTCRe-check
6 Nov 16:50 UTC2.32 km Forecast7 Nov 17:02 UTC5 Nov 20:01 UTCRe-check
6 Nov 16:30 UTC2.88 km Forecast7 Nov 16:30 UTC5 Nov 20:01 UTCScreen

These Objects Elsewhere

Other screened approaches · 7 days
1.27 km11-06 17:33 UTC
SJ-30CREASON-1
1.95 km11-10 21:20 UTC
W-SERIES 9OBJECT CK
2.73 km11-05 01:26 UTC
REASON-1CZ-2C R/B

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 →