| Primary satellite | Secondary satellite |
| Name | ESTCUBE 1 | COSMOS 2251 DEB |
| Spacetrack catalog number | 39161 | 33999 |
| Radar cross section | small | small |
| Epoch of two-line elements (UTC) | 2023 May 31 22:21 | 2023 May 31 15:36 |
| Time of closest approach (UTC) | 2023 Apr 01 20:50:41.898 |
| Minimum distance | 176.897 km |
| Height difference | -2.542 km |
| Relative speed | 15.030 km/s |
| Angle between velocity vectors | 170° |
| Geographic position | 39.6°N, 17.2°E |
| Height | 661 km |
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