| Primary satellite | Secondary satellite |
| Name | USA 281 | Altair 2 |
| Spacetrack catalog number | 43145 | 2755 |
| Radar cross section | | medium |
| Epoch of two-line elements (UTC) | 2021 Apr 03 21:44 | 2021 Apr 12 12:56 |
| Time of closest approach (UTC) | 2021 Mar 03 14:41:58.571 |
| Minimum distance | 3.060 km |
| Height difference | -2.915 km |
| Relative speed | 13.869 km/s |
| Angle between velocity vectors | 143° |
| Geographic position | 62.4°N, 12.6°W |
| Height | 1090 km |
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