| Primary satellite | Secondary satellite |
| Name | Cosmos 1125 Rocket | IRIDIUM 148 |
| Spacetrack catalog number | 11511 | 43255 |
| Radar cross section | large | large |
| Epoch of two-line elements (UTC) | 2021 Jan 20 12:05 | 2021 Jan 20 11:02 |
| Time of closest approach (UTC) | 2020 Dec 04 03:25:39.447 |
| Minimum distance | 53.146 km |
| Height difference | -3.430 km |
| Relative speed | 10.715 km/s |
| Angle between velocity vectors | 92° |
| Geographic position | 73.5°S, 83.1°W |
| Height | 807 km |
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