| Primary satellite | Secondary satellite |
| Name | Cosmos 841 Rocket | COSMOS 2251 DEB |
| Spacetrack catalog number | 9023 | 34874 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Jan 16 12:52 | 2021 Jan 15 22:27 |
| Time of closest approach (UTC) | 2020 Nov 28 22:37:17.186 |
| Minimum distance | 13.347 km |
| Height difference | -5.530 km |
| Relative speed | 11.804 km/s |
| Angle between velocity vectors | 104° |
| Geographic position | 63.4°S, 96.7°E |
| Height | 787 km |
|