| Primary satellite | Secondary satellite |
| Name | CZ-2D R/B | Cosmos 1238 Rocket |
| Spacetrack catalog number | 28738 | 12139 |
| Radar cross section | large | large |
| Epoch of two-line elements (UTC) | 2021 Jan 17 18:50 | 2021 Jan 17 20:33 |
| Time of closest approach (UTC) | 2020 Dec 03 18:13:19.903 |
| Minimum distance | 3.063 km |
| Height difference | -0.028 km |
| Relative speed | 15.267 km/s |
| Angle between velocity vectors | 178° |
| Geographic position | 13.9°S, 172.6°W |
| Height | 539 km |
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