| Primary satellite | Secondary satellite |
| Name | Cosmos 2151 Rocket | COSMOS 2251 DEB |
| Spacetrack catalog number | 21423 | 35587 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Jan 19 16:56 | 2021 Jan 18 23:16 |
| Time of closest approach (UTC) | 2020 Dec 02 06:45:59.311 |
| Minimum distance | 11.735 km |
| Height difference | 0.705 km |
| Relative speed | 14.269 km/s |
| Angle between velocity vectors | 142° |
| Geographic position | 50.7°S, 37.8°E |
| Height | 655 km |
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