| Primary satellite | Secondary satellite |
| Name | Cosmos 1603 | deb Delta 139 |
| Spacetrack catalog number | 15333 | 12166 |
| Radar cross section | large | medium |
| Epoch of two-line elements (UTC) | 2021 Jan 25 11:40 | 2021 Jan 25 13:25 |
| Time of closest approach (UTC) | 2020 Nov 29 11:14:38.658 |
| Minimum distance | 345.477 km |
| Height difference | 2.908 km |
| Relative speed | 3.781 km/s |
| Angle between velocity vectors | 30° |
| Geographic position | 16.5°S, 87.8°E |
| Height | 853 km |
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