| Primary satellite | Secondary satellite |
| Name | SKYMED 3 | Helios 1B |
| Spacetrack catalog number | 33412 | 25977 |
| Radar cross section | large | large |
| Epoch of two-line elements (UTC) | 2021 Apr 11 18:08 | 2021 Apr 11 09:49 |
| Time of closest approach (UTC) | 2021 Mar 05 19:28:30.299 |
| Minimum distance | 109.149 km |
| Height difference | -1.752 km |
| Relative speed | 1.937 km/s |
| Angle between velocity vectors | 15° |
| Geographic position | 81.6°S, 137.5°W |
| Height | 650 km |
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