| 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 22 17:16 | 2021 Jan 22 18:22 |
| Time of closest approach (UTC) | 2020 Nov 30 05:44:41.356 |
| Minimum distance | 157.653 km |
| Height difference | 3.106 km |
| Relative speed | 7.783 km/s |
| Angle between velocity vectors | 63° |
| Geographic position | 65.7°S, 63.4°W |
| Height | 892 km |
|