| Primary satellite | Secondary satellite |
| Name | First-Move | COSMOS 2251 DEB |
| Spacetrack catalog number | 39439 | 34791 |
| Radar cross section | small | small |
| Epoch of two-line elements (UTC) | 2021 Feb 27 12:52 | 2021 Feb 27 04:38 |
| Time of closest approach (UTC) | 2021 Jan 17 13:36:59.299 |
| Minimum distance | 24.189 km |
| Height difference | 1.442 km |
| Relative speed | 15.059 km/s |
| Angle between velocity vectors | 171° |
| Geographic position | 14.2°N, 47.6°E |
| Height | 617 km |
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