| Primary satellite | Secondary satellite |
| Name | Cosmos 1727 Rocket | Kosmos-400 |
| Spacetrack catalog number | 16511 | 5050 |
| Radar cross section | large | large |
| Epoch of two-line elements (UTC) | 2026 Jan 13 13:12 | 2026 Jan 13 13:05 |
| Time of closest approach (UTC) | 2025 Dec 22 22:11:28.185 |
| Minimum distance | 0.992 km |
| Height difference | -0.712 km |
| Relative speed | 14.066 km/s |
| Angle between velocity vectors | 146° |
| Geographic position | 22.1°N, 11.0°E |
| Height | 997 km |
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