| Primary satellite | Secondary satellite |
| Name | Cosmos 1125 Rocket | COSMOS 2251 DEB |
| Spacetrack catalog number | 11511 | 34796 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Apr 09 22:36 | 2021 Apr 09 20:28 |
| Time of closest approach (UTC) | 2021 Mar 07 01:08:51.499 |
| Minimum distance | 10.057 km |
| Height difference | 3.840 km |
| Relative speed | 13.021 km/s |
| Angle between velocity vectors | 122° |
| Geographic position | 55.7°N, 179.9°E |
| Height | 789 km |
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