DELTA 1 R/B
| Launched | 20 June 1975 |
| Flight ended | 8 April 1981 |
| Status | Decayed |
| Launch site | Air Force Eastern Test Range, Florida, USA |
| Owner | United States |
| NORAD ID | 7971 |
| COSPAR ID | 1975-057B |
| Observing |
Launched alongside
OSO 8DELTA 1 R/B
| Launched | 20 June 1975 |
| Flight ended | 8 April 1981 |
| Status | Decayed |
| Launch site | Air Force Eastern Test Range, Florida, USA |
| Owner | United States |
| NORAD ID | 7971 |
| COSPAR ID | 1975-057B |
| Observing |
Launched alongside
OSO 8