| Primary satellite | Secondary satellite |
| Name | ALOS | COSMOS 2251 DEB |
| Spacetrack catalog number | 28931 | 39548 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Jan 17 20:48 | 2020 Dec 18 21:34 |
| Time of closest approach (UTC) | 2020 Dec 04 19:54:21.045 |
| Minimum distance | 8.210 km |
| Height difference | 1.150 km |
| Relative speed | 12.987 km/s |
| Angle between velocity vectors | 120° |
| Geographic position | 74.0°N, 84.0°W |
| Height | 698 km |
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