HomeManeuver TrackerClose ApproachesUSA 283 ⟷ APSTAR 6C
high · CROSS-BORDER
9.96 kmmiss distance
Closest approach (TCA)
2026-09-19 11:47 UTC
Relative speed
0.00 km/s
Altitude
Current separation
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On 2026-09-19 11:47 UTC, US USA 283 and CN APSTAR 6C reached a closest approach (TCA) of 9.96 km, with a relative velocity of 0.00 km/s. This is a cross-border encounter between objects of different nations, the kind of event closely watched for space-security implications. 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 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
USA 283Payload
NORAD 43339
CountryUS
Launched2018-04-14
COSPAR2018-036A
Maneuver capableUnknown
APSTAR 6CPayload
NORAD 43450
CountryPRC
Launched2018-05-03
COSPAR2018-041A
Maneuver capableUnknown

Where This Happens

Altitude context
GEO BELT 35,786 KMTHIS PASS · 35,786 KMLEOMEOGEO

This pass happens near the geostationary belt, where satellites hold fixed longitude slots and relative speeds are low. Close approaches here are usually slow drifts rather than crossing passes. About GEO →

History Between This Pair

2 recorded passes under 10 km
Pair history · USA 283 ⟷ APSTAR 6C
Now4.91 km0.00 km/s35,786 kmThis page
Now9.96 km0.00 km/s35,786 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
6.00 km09-20 09:53 UTC
USA 283APSTAR 6E
6.31 km09-18 10:01 UTC
USA 283APSTAR 6E
6.52 km09-17 09:56 UTC
USA 283APSTAR 6E

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 — “USA 283 ⟷ APSTAR 6C: 9.96 km close approach”, https://orbitalradar.com/conjunction/43339-43450 (accessed 2026-09-20).