| Primary satellite | Secondary satellite |
| Name | Cosmos 1666 Rocket | STARS |
| Spacetrack catalog number | 15890 | 33498 |
| Radar cross section | large | medium |
| Epoch of two-line elements (UTC) | 2025 Jun 22 14:09 | 2025 Jun 22 15:58 |
| Time of closest approach (UTC) | 2024 Jul 25 16:09:59.924 |
| Minimum distance | 4012.067 km |
| Height difference | -7.228 km |
| Relative speed | 14.428 km/s |
| Angle between velocity vectors | 145° |
| Geographic position | 49.8°S, 155.6°E |
| Height | 619 km |
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