| Primary satellite | Secondary satellite |
| Name | Cosmos 1603 | deb Kosmos-1275 |
| Spacetrack catalog number | 15333 | 12658 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Jan 25 11:40 | 2021 Jan 25 10:31 |
| Time of closest approach (UTC) | 2020 Nov 30 11:42:19.944 |
| Minimum distance | 1045.048 km |
| Height difference | -7.656 km |
| Relative speed | 2.739 km/s |
| Angle between velocity vectors | 21° |
| Geographic position | 46.4°N, 117.5°W |
| Height | 843 km |
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