| Primary satellite | Secondary satellite |
| Name | YUBILEINY | Kosmos-1638 |
| Spacetrack catalog number | 32953 | 15620 |
| Radar cross section | medium | medium |
| Epoch of two-line elements (UTC) | 2026 Jan 19 07:03 | 2026 Jan 19 00:21 |
| Time of closest approach (UTC) | 2025 Dec 17 10:52:32.020 |
| Minimum distance | 3.821 km |
| Height difference | -3.753 km |
| Relative speed | 13.878 km/s |
| Angle between velocity vectors | 154° |
| Geographic position | 25.3°S, 144.5°W |
| Height | 1488 km |
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