| Primary satellite | Secondary satellite |
| Name | Cosmos 1603 | FENGYUN 1C DEB |
| Spacetrack catalog number | 15333 | 30448 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Apr 10 02:44 | 2021 Apr 10 15:06 |
| Time of closest approach (UTC) | 2021 Mar 09 12:44:15.898 |
| Minimum distance | 34.865 km |
| Height difference | -3.274 km |
| Relative speed | 3.584 km/s |
| Angle between velocity vectors | 28° |
| Geographic position | 3.9°S, 55.6°W |
| Height | 854 km |
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