| Primary satellite | Secondary satellite |
| Name | Transit 4A | COSMOS 2251 DEB |
| Spacetrack catalog number | 116 | 33896 |
| Radar cross section | medium | small |
| Epoch of two-line elements (UTC) | 2021 Jan 23 08:47 | 2021 Jan 23 07:22 |
| Time of closest approach (UTC) | 2020 Nov 30 05:44:40.330 |
| Minimum distance | 159.257 km |
| Height difference | 3.134 km |
| Relative speed | 7.785 km/s |
| Angle between velocity vectors | 63° |
| Geographic position | 65.7°S, 63.4°W |
| Height | 892 km |
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