| Primary satellite | Secondary satellite |
| Name | ARGOS | COSMOS 2251 DEB |
| Spacetrack catalog number | 25634 | 35890 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Apr 09 19:37 | 2021 Apr 07 15:06 |
| Time of closest approach (UTC) | 2021 Mar 05 11:41:12.322 |
| Minimum distance | 13.897 km |
| Height difference | 1.491 km |
| Relative speed | 14.483 km/s |
| Angle between velocity vectors | 155° |
| Geographic position | 68.1°S, 140.0°E |
| Height | 848 km |
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