| Primary satellite | Secondary satellite |
| Name | Cosmos 1666 | LEMUR 2 EJATTA |
| Spacetrack catalog number | 15889 | 44409 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2023 Feb 01 06:47 | 2023 Feb 01 12:04 |
| Time of closest approach (UTC) | 2022 Dec 03 19:22:29.034 |
| Minimum distance | 983.259 km |
| Height difference | 8.454 km |
| Relative speed | 14.269 km/s |
| Angle between velocity vectors | 140° |
| Geographic position | 78.6°N, 52.6°W |
| Height | 520 km |
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