| Primary satellite | Secondary satellite |
| Name | Cosmos 1328 | KEPLER-4 (ANTILLES) |
| Spacetrack catalog number | 12987 | 46498 |
| Radar cross section | large | medium |
| Epoch of two-line elements (UTC) | 2023 Sep 22 04:33 | 2023 Sep 21 22:33 |
| Time of closest approach (UTC) | 2023 Jun 01 00:17:40.995 |
| Minimum distance | 40.355 km |
| Height difference | -24.729 km |
| Relative speed | 15.157 km/s |
| Angle between velocity vectors | 180° |
| Geographic position | 61.0°S, 13.0°E |
| Height | 570 km |
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