| Primary satellite | Secondary satellite |
| Name | COSMOS 2251 DEB | Vanguard 3 |
| Spacetrack catalog number | 38001 | 20 |
| Radar cross section | small | medium |
| Epoch of two-line elements (UTC) | 2024 Dec 19 14:25 | 2024 Dec 23 08:13 |
| Time of closest approach (UTC) | 2024 Dec 24 13:27:40.602 |
| Minimum distance | 3.685 km |
| Height difference | -0.394 km |
| Relative speed | 7.805 km/s |
| Angle between velocity vectors | 60° |
| Geographic position | 31.6°N, 179.7°W |
| Height | 620 km |
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