| 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 02 05:09 |
| Time of closest approach (UTC) | 2021 Jan 19 05:29:43.068 |
| Minimum distance | 9.030 km |
| Height difference | 3.651 km |
| Relative speed | 14.632 km/s |
| Angle between velocity vectors | 157° |
| Geographic position | 76.5°N, 118.5°W |
| Height | 789 km |
|