ESRO-4
| Launched | 21 November 1972 |
| Flight ended | 14 April 1974 |
| Status | Decayed |
| Launch site | Air Force Western Test Range, California, USA |
| Owner | European Space Research Organization |
| NORAD ID | 6285 |
| COSPAR ID | 1972-092A |
| Observing |
Launched alongside
SCOUT D-1 R/B