| Greenhouse Item | |
|---|---|
 | |
| Information | |
| Country | United States |
| Test series | Operation Greenhouse |
| Test site | Enewetak |
| Date | May 25, 1951 |
| Test type | Atmospheric |
| Yield | 45.5 kt |
| Test chronology | |
Greenhouse-Item was an American nuclear test conducted on May 25, 1951, as part of Operation Greenhouse at the Pacific Proving Ground, specifically on the island of Engebi in the Eniwetok Atoll in the Central Pacific Ocean. This test explosion was the second test of a boosted fission weapon, the second instance of artificial thermonuclear fusion, following the Greenhouse George test on May 9.