| Primary satellite | Secondary satellite |
| Name | ALOS | COSMOS 2251 DEB |
| Spacetrack catalog number | 28931 | 37538 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Jan 17 20:48 | 2021 Jan 17 14:48 |
| Time of closest approach (UTC) | 2020 Dec 08 02:41:28.434 |
| Minimum distance | 21.679 km |
| Height difference | 1.379 km |
| Relative speed | 14.479 km/s |
| Angle between velocity vectors | 149° |
| Geographic position | 70.8°N, 179.5°E |
| Height | 698 km |
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