| Primary satellite | Secondary satellite |
| Name | Cosmos 1975 Rocket | HODOYOSHI 4 |
| Spacetrack catalog number | 19574 | 40011 |
| Radar cross section | large | medium |
| Epoch of two-line elements (UTC) | 2021 Jan 17 16:33 | 2021 Jan 18 03:33 |
| Time of closest approach (UTC) | 2020 Dec 03 21:28:18.155 |
| Minimum distance | 3.131 km |
| Height difference | -2.425 km |
| Relative speed | 15.093 km/s |
| Angle between velocity vectors | 180° |
| Geographic position | 30.7°N, 178.1°W |
| Height | 629 km |
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