| Primary satellite | Secondary satellite |
| Name | Cosmos 1726 Rocket | ERS 1 DEB |
| Spacetrack catalog number | 16496 | 35258 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Mar 08 19:03 | 2021 Mar 08 00:56 |
| Time of closest approach (UTC) | 2021 Jan 23 01:22:35.454 |
| Minimum distance | 1.920 km |
| Height difference | -0.162 km |
| Relative speed | 14.715 km/s |
| Angle between velocity vectors | 155° |
| Geographic position | 81.8°S, 8.4°E |
| Height | 653 km |
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