| Primary satellite | Secondary satellite |
| Name | Transit 4A | Cosmos 1809 |
| Spacetrack catalog number | 116 | 17241 |
| Radar cross section | medium | large |
| Epoch of two-line elements (UTC) | 2026 Jan 18 21:59 | 2026 Jan 18 18:48 |
| Time of closest approach (UTC) | 2025 Dec 19 01:59:53.543 |
| Minimum distance | 9.129 km |
| Height difference | -1.484 km |
| Relative speed | 10.362 km/s |
| Angle between velocity vectors | 89° |
| Geographic position | 65.7°S, 142.9°E |
| Height | 968 km |
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