| Primary satellite | Secondary satellite |
| Name | Cosmos 1666 Rocket | VOLGA DEB |
| Spacetrack catalog number | 15890 | 44621 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2025 Jun 14 08:55 | 2025 Jun 13 19:50 |
| Time of closest approach (UTC) | 2024 Jul 26 05:35:11.332 |
| Minimum distance | 2290.198 km |
| Height difference | -45.063 km |
| Relative speed | 12.314 km/s |
| Angle between velocity vectors | 109° |
| Geographic position | 67.2°N, 124.0°E |
| Height | 638 km |
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