| Primary satellite | Secondary satellite |
| Name | CZ-4 R/B | COSMOS 2251 DEB |
| Spacetrack catalog number | 29507 | 37093 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Apr 12 19:39 | 2021 Apr 12 01:26 |
| Time of closest approach (UTC) | 2021 Mar 05 23:52:27.026 |
| Minimum distance | 34.228 km |
| Height difference | -1.838 km |
| Relative speed | 13.713 km/s |
| Angle between velocity vectors | 129° |
| Geographic position | 73.5°S, 82.3°E |
| Height | 602 km |
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