| Primary satellite | Secondary satellite |
| Name | SHIYUAN 3 (SY-3) | IRIDIUM 121 |
| Spacetrack catalog number | 33433 | 42812 |
| Radar cross section | medium | large |
| Epoch of two-line elements (UTC) | 2024 Dec 23 02:19 | 2024 Dec 22 16:39 |
| Time of closest approach (UTC) | 2024 Dec 26 20:37:35.395 |
| Minimum distance | 2.185 km |
| Height difference | -1.993 km |
| Relative speed | 14.728 km/s |
| Angle between velocity vectors | 162° |
| Geographic position | 72.2°S, 4.2°E |
| Height | 808 km |
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