| Primary satellite | Secondary satellite |
| Name | Cosmos 1603 | COSMOS 1275 DEB |
| Spacetrack catalog number | 15333 | 42156 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Jan 23 22:19 | 2021 Jan 23 15:49 |
| Time of closest approach (UTC) | 2020 Dec 01 06:58:05.186 |
| Minimum distance | 151.618 km |
| Height difference | -1.949 km |
| Relative speed | 12.374 km/s |
| Angle between velocity vectors | 113° |
| Geographic position | 65.6°S, 21.0°E |
| Height | 884 km |
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