| Primary satellite | Secondary satellite |
| Name | Cosmos 1603 | Star 26B S/N 006 |
| Spacetrack catalog number | 15333 | 7219 |
| Radar cross section | large | large |
| Epoch of two-line elements (UTC) | 2026 Jan 13 09:55 | 2026 Jan 13 14:59 |
| Time of closest approach (UTC) | 2025 Dec 18 08:55:08.413 |
| Minimum distance | 4.620 km |
| Height difference | 3.355 km |
| Relative speed | 12.976 km/s |
| Angle between velocity vectors | 122° |
| Geographic position | 71.1°S, 111.8°E |
| Height | 874 km |
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