ESRO 2B
| Mission type | Astrophysics |
|---|---|
| Operator | ESRO |
| COSPAR ID | 1968-041A |
| SATCAT no. | 03233 |
| Spacecraft properties | |
| Launch mass | 89.8 kilograms (198 lb) |
| Start of mission | |
| Launch date | 17 May 1968, 02:06:00 UTC |
| Rocket | Scout B |
| Launch site | Vandenberg SLC-5 |
| End of mission | |
| Decay date | 8 May 1971, shortly after 03:00 UT |
| Orbital parameters | |
| Reference system | Geocentric |
| Regime | Low Earth |
| Perigee altitude | 326 kilometres (203 mi) |
| Apogee altitude | 1,086 kilometres (675 mi) |
| Inclination | 97.2 degrees |
| Period | 98.9 minutes |
| Epoch | 16 May 1968, 22:09:00 UTC |
ESRO-2B or Iris (International Radiation Investigation Satellite; sometimes Iris 2) or sometimes ESRO II (or ESRO 2), was a European astrophysical spin-stabilised research satellite which was launched in 1968. Operated by the European Space Research Organisation, ESRO 2B made astronomical surveys primarily in x-ray and solar particles detectors.