| Primary satellite | Secondary satellite |
| Name | Envisat | COSMOS 2251 DEB |
| Spacetrack catalog number | 27386 | 34990 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Jan 20 00:47 | 2021 Jan 13 13:45 |
| Time of closest approach (UTC) | 2020 Dec 01 12:49:47.717 |
| Minimum distance | 18.406 km |
| Height difference | 2.701 km |
| Relative speed | 8.160 km/s |
| Angle between velocity vectors | 66° |
| Geographic position | 67.1°S, 91.3°E |
| Height | 790 km |
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