Home›Maneuver Tracker›Close Approaches›UMBRA-13 ⟷ CESARIO
MediumProximity
Final forecastFinal forecast, made 13 min before the pass.
Closest approach12 Nov 202609:36 UTC
Relative speed5.84 km/sat the closest approach
Altitude590 kmlow Earth orbit
Last confirmed12 Nov09:23 UTC · final forecast

US UMBRA-13 and POR CESARIO were predicted to reach a closest approach of 5.96 km at 2026-11-12 09:36 UTC, at a relative speed of 5.84 km/s. Final forecast, made 13 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
UMBRA-13Payload
NORAD 101129
CountryUS
Launched2026-10-20
COSPAR2026-237U
Maneuver capableUnknown
CESARIOPayload
NORAD 100642
CountryPOR
Launched2026-07-07
COSPAR2026-156CE
Maneuver capableUnknown

Where This Happens

Altitude context
DEBRIS BELT 700–1000 KM2006001,0001,5002,000 kmTHIS PASS · 590 KMISS 420Starlink 550

At 590 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 · UMBRA-13 ⟷ CESARIO
2026-11-12 12:002.40 km Final forecast5.83 km/s592 kmView →
2026-11-12 09:365.96 km Final forecast5.84 km/s590 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 Nothing is overwritten: a withdrawn forecast keeps its figure, with the newer check beside it, and the best estimate after the pass is a row of its own.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
12 Nov 09:12 UTC5.96 km Forecast12 Nov 09:36 UTC11 Nov 22:23 UTCRe-check
11 Nov 22:18 UTC6.04 km Forecast12 Nov 09:36 UTC11 Nov 15:57 UTCRe-check
11 Nov 11:57 UTC6.18 km Forecast12 Nov 09:36 UTC11 Nov 01:31 UTCRe-check
11 Nov 11:37 UTC7.12 km Forecast12 Nov 09:36 UTC11 Nov 01:31 UTCScreen

These Objects Elsewhere

Other screened approaches · 7 days
929 m11-13 07:44 UTC
SPEAR-1CCESARIO
1.10 km11-14 13:56 UTC
UMBRA-14CESARIO
1.29 km11-15 06:56 UTC
UMBRA-13CZ-6A 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 →