| Primary satellite | Secondary satellite |
| Name | COSMOS 2251 DEB | ASTEX 1 |
| Spacetrack catalog number | 33938 | 5560 |
| Radar cross section | small | large |
| Epoch of two-line elements (UTC) | 2024 Dec 23 12:12 | 2024 Dec 23 11:53 |
| Time of closest approach (UTC) | 2024 Dec 25 06:37:46.665 |
| Minimum distance | 2.895 km |
| Height difference | 2.568 km |
| Relative speed | 13.731 km/s |
| Angle between velocity vectors | 134° |
| Geographic position | 70.4°S, 176.5°W |
| Height | 762 km |
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