| Primary satellite | Secondary satellite |
| Name | Cosmos 2181 Rocket | FENGYUN 1C DEB |
| Spacetrack catalog number | 21903 | 30937 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Apr 16 21:07 | 2021 Apr 17 01:53 |
| Time of closest approach (UTC) | 2021 Mar 04 00:25:56.254 |
| Minimum distance | 3.244 km |
| Height difference | 0.901 km |
| Relative speed | 14.558 km/s |
| Angle between velocity vectors | 163° |
| Geographic position | 78.8°S, 52.3°E |
| Height | 979 km |
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