| Primary satellite | Secondary satellite |
| Name | Vanguard 2 | COSMOS 2251 DEB |
| Spacetrack catalog number | 11 | 34303 |
| Radar cross section | medium | small |
| Epoch of two-line elements (UTC) | 2024 Dec 08 12:41 | 2024 Dec 08 12:35 |
| Time of closest approach (UTC) | 2024 Nov 10 21:22:48.360 |
| Minimum distance | 466.119 km |
| Height difference | -26.282 km |
| Relative speed | 12.526 km/s |
| Angle between velocity vectors | 107° |
| Geographic position | 4.9°N, 126.9°E |
| Height | 658 km |
|