| Primary satellite | Secondary satellite |
| Name | STRAND 1 | IRIDIUM 135 |
| Spacetrack catalog number | 39090 | 43070 |
| Radar cross section | small | large |
| Epoch of two-line elements (UTC) | 2021 Mar 01 09:54 | 2021 Mar 01 14:05 |
| Time of closest approach (UTC) | 2021 Jan 19 08:50:35.026 |
| Minimum distance | 3.569 km |
| Height difference | 3.549 km |
| Relative speed | 14.637 km/s |
| Angle between velocity vectors | 157° |
| Geographic position | 76.3°N, 169.4°W |
| Height | 789 km |
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