| Primary satellite | Secondary satellite |
| Name | Vanguard 1 | deb Agena D |
| Spacetrack catalog number | 5 | 4611 |
| Radar cross section | medium | medium |
| Epoch of two-line elements (UTC) | 2021 Jan 16 09:33 | 2021 Jan 16 12:02 |
| Time of closest approach (UTC) | 2020 Dec 08 15:54:07.406 |
| Minimum distance | 49.718 km |
| Height difference | 6.901 km |
| Relative speed | 12.305 km/s |
| Angle between velocity vectors | 107° |
| Geographic position | 34.1°N, 166.3°W |
| Height | 924 km |
|