| Primary satellite | Secondary satellite |
| Name | Cosmos 1891 Rocket | FENGYUN 1C DEB |
| Spacetrack catalog number | 18403 | 46445 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Jan 17 20:38 | 2020 Dec 28 11:22 |
| Time of closest approach (UTC) | 2020 Nov 30 20:47:19.248 |
| Minimum distance | 16.918 km |
| Height difference | 3.630 km |
| Relative speed | 14.729 km/s |
| Angle between velocity vectors | 175° |
| Geographic position | 76.4°S, 60.2°E |
| Height | 961 km |
|