| Primary satellite | Secondary satellite |
| Name | Cosmos 1844 Rocket | COSMOS 2251 DEB |
| Spacetrack catalog number | 17974 | 35593 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Jan 16 18:17 | 2021 Jan 16 08:44 |
| Time of closest approach (UTC) | 2020 Dec 08 02:29:07.484 |
| Minimum distance | 19.858 km |
| Height difference | 2.394 km |
| Relative speed | 14.004 km/s |
| Angle between velocity vectors | 141° |
| Geographic position | 26.8°S, 170.5°W |
| Height | 838 km |
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