| Primary satellite | Secondary satellite |
| Name | Cosmos 1937 Rocket | COSMOS 2251 DEB |
| Spacetrack catalog number | 19039 | 37280 |
| Radar cross section | large | small |
| Epoch of two-line elements (UTC) | 2021 Jan 18 01:40 | 2021 Jan 17 14:50 |
| Time of closest approach (UTC) | 2020 Dec 01 11:33:03.132 |
| Minimum distance | 9.068 km |
| Height difference | 0.499 km |
| Relative speed | 8.396 km/s |
| Angle between velocity vectors | 68° |
| Geographic position | 70.7°S, 123.1°E |
| Height | 791 km |
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