Hiroshima and nagasaki bomb dates

How it works

Those are calendar facts, not a range you can slide. Hiroshima is August 6. Nagasaki is August 9. In Hiroshima local time the first bomb, a uranium device called Little Boy, was dropped from the B-29 Enola Gay and exploded in the morning, about 8:15 a.m. In Nagasaki local time the second bomb, a plutonium device called Fat Man, was dropped from the B-29 Bockscar and exploded in the late morning, about 11:02 a.m. Kokura had been the primary target that day; cloud and smoke sent the aircraft to Nagasaki instead.

The two bombings are the only use of nuclear weapons in war to date. Japan’s emperor announced surrender on August 15, 1945, Japan time. Formal surrender followed on September 2, 1945, aboard USS Missouri in Tokyo Bay. The August pair is the question this page answers. Do not collapse August 6 and August 9 into one anniversary, and do not move them to July because another wartime date sits nearby.

Anniversaries return every year on those civil dates. Hiroshima holds a peace ceremony on August 6. Nagasaki holds one on August 9. If you are counting days until the next mark, count to the date you mean, not to “the bombings” as a single blob. Time zones will shift the clock hour for a live broadcast. They will not shift the local calendar date in Japan.

Two cities, two days, one August

August 6, 7, and 8 sit between the two attacks. That gap is part of the history: a second mission three days later, not a simultaneous pair. People who remember only “August 1945” lose the order. Order matters if you are placing the dates on a timeline next to the Soviet declaration of war against Japan on August 8 and the Nagasaki mission on August 9.

Casualty totals vary by counting method and by how late after the blasts deaths are included. This page will not invent a round number and call it the count. What is not in dispute is that each city was struck on the morning of its date, that the weapons were nuclear, and that tens of thousands of people were killed in each city in the immediate period, with more dying later from injuries and radiation. Memorials in both cities exist so the dates are not only a trivia pair.

Hiroshima: August 6, 1945, morning, Little Boy, Enola Gay. Nagasaki: August 9, 1945, late morning, Fat Man, Bockscar; Kokura had been first on the list. Surrender announced: August 15, 1945, Japan time.

Anniversaries: the same civil dates each year in those cities. August 6 is not August 9. The calendar keeps three days between them, and the two cities are not interchangeable marks.

How to write the dates without flattening them

Write both names and both days. “Hiroshima, August 6, 1945; Nagasaki, August 9, 1945” is complete. “The bomb dates” is not. If a form asks for one date, it is asking the wrong question. If you are setting a reminder, set two. If you are teaching the week, put August 6, then the days in between, then August 9, then August 15. The month is August. The year is 1945. Those four numbers do not move.

Other nuclear dates — tests in other years, other countries — are other dates. They do not relocate these two. The Gregorian calendar in use for these civil dates is the same calendar that still prints August 6 and August 9 every year. The history sits on those squares. Keep them separate when you speak, the way the week kept them separate when they happened.