Conversation so far:
when were the atomic bombs dropped on hiroshima and nagasaki
The United States detonated two nuclear weapons over the Japanese cities of Hiroshima and Nagasaki on August 6 and 9, 1945.
how many people were killed in the atomic bombings of hiroshima and nagasaki
The atomic bombings of Hiroshima and Nagasaki killed between 129,000 and 226,000 people.

Question: what was the first bomb called
Self-contained rewrite: what was the atomic bomb dropped on hiroshima called