| Primary satellite | Secondary satellite |
| Name | Envisat | COSMOS 2251 DEB |
| Spacetrack catalog number | 27386 | 33842 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Apr 16 14:23 | 2021 Apr 16 10:21 |
| Time of closest approach (UTC) | 2021 Mar 09 10:24:30.378 |
| Minimum distance | 5.541 km |
| Height difference | 3.846 km |
| Relative speed | 13.272 km/s |
| Angle between velocity vectors | 126° |
| Geographic position | 74.0°S, 134.0°E |
| Height | 792 km |
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