| Primary satellite | Secondary satellite |
| Name | ARGOS | COSMOS 2251 DEB |
| Spacetrack catalog number | 25634 | 36061 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Apr 14 02:49 | 2021 Apr 12 01:05 |
| Time of closest approach (UTC) | 2021 Mar 03 15:30:55.025 |
| Minimum distance | 11.639 km |
| Height difference | -0.064 km |
| Relative speed | 14.447 km/s |
| Angle between velocity vectors | 153° |
| Geographic position | 69.6°S, 142.2°W |
| Height | 845 km |
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