| Nimbus B | |
| Mission Type: | Weather satellite |
| Operator: | NASA |
| Cospar Id: | NIMBS-B |
| Mission Duration: | Launch failure |
| Manufacturer: | RCA Astrospace |
| Launch Mass: | [1] |
| Launch Date: | UTC[2] |
| Launch Rocket: | Thorad-SLV2G Agena-D |
| Launch Site: | Vandenberg SLC-2E |
| Orbit Epoch: | Planned |
| Orbit Reference: | Geocentric |
| Orbit Regime: | Low Earth |
| Apsis: | gee |
| Programme: | Nimbus program |
| Previous Mission: | Nimbus 2 |
| Next Mission: | Nimbus 3 |
Nimbus B was a meteorological satellite launched as part of the Nimbus program. It was released on May 18, 1968 from the Vandenberg Air Force Base, Lompoc, California, by means of a Thor-Agena launch vehicle, together with the SECOR 10 satellite. Nimbus B never achieved orbit because a malfunction in the booster guidance system forced the destruction of the spacecraft and its payload during launch.
The Radioisotope Thermoelectric Generator SNAP-19 RTG was salvaged from the water, refurbished and later flown on Nimbus 3.[3]