12 August 2005
This past week saw the 60th anniversary of the dropping of the atomic bombs on Hiroshima and Nagasaki, the events that brought an end to World War II. These two grim events introduced a large number of terms in the vocabularies of millions.
First among these are the names for the device itself. The term atomic bomb predates the device, being used as early as 1914 in H.G. Wells’s The World Set Free. Its shorter cousin A-bomb dates from 1945 as does the term the bomb. The thermonuclear hydrogen bomb comes a few years later in 1947 and H-bomb in 1950. The use of more technically accurate nuclear to denote fission and fusion processes and weapons also comes in 1945.
Much of the jargon of the scientists and engineers constructing the bombs also made its way into the vernacular. The Manhattan Project was the name of the secret project, so-called because finance office responsible for paying the bills was located in the Manhattan district offices of the Army Corps of Engineers. The individual bombs had their own names too. The first device, code-named Trinity, was detonated at Alamogordo, New Mexico on 16 July 1945. The scientists who built it simply called it the gadget. The bomb dropped on Hiroshima on 6 August 1945 was called Little Boy. Three days later Fat Man, so-called because of its round shape, was dropped on Nagasaki. The Soviet Union declared war on Japan the following day and the Japanese surrendered on 15 August. Historians have long debated which event was more important in prompting the surrender, the dropping of the atomic bombs or the Soviet declaration of war and invasion of Japanese-occupied Manchuria.
The power of atomic weapons also created a couple of terms to describe the unprecedented size of the explosions. A kiloton is the explosive power equivalent to one thousand tons of TNT. The term dates to 1950. The Hiroshima bomb was somewhere between twelve and fifteen kilotons. The Nagasaki bomb was larger at somewhere just above twenty kilotons. (The unclassified yield of a modern US nuclear strategic warhead is 300 kilotons.) In 1952 the term megaton was coined to denote explosive power equivalent to one million tons of TNT.
While the explosive power, or blast, of an atomic weapon is its most spectacular feature, it is not the only effect. Radiation is a significant hazard. The term fall-out was coined in 1950 to describe the radioactive particles of dirt and dust that are sucked into the fireball and which eventually touch down, often many miles away from the detonation. The less well-known rain-out was coined in 1954 to denote fall-out that was prematurely flushed from the atmosphere by rain.
The effects of excessive radiation on the human body can be deadly. The term radiation sickness describing some of these effects has been around since 1924. The term radiation burn, seen on many of the survivors of the bombings, dates to 1949. Since radiation cannot be detected without instruments, various devices are needed to measure radiactivity. Radiation counter dates to 1947, as does radiation meter. Radiation monitor comes a bit later in 1951. The more familiar Geiger counter, named after physicist Hans Geiger, is older, dating to 1924.
But atomic weapons have other effects as well. Notable are the thermal effects, or heat and fire—both direct from the detonation and secondary from fires started by the heat of the blast. The term fire storm was known well before the atomic age, being used as a descriptive term for a great fire since the 16th century. Modern use of the term to refer to an all-consuming conflagration caused by bombs dates to 1945. Fire storms are not unique to atomic weapons; the incendiary bombings of Dresden and Tokyo also created fire storms.
Atomic weapons also have electromagnetic effects, but these weren’t fully appreciated early in the atomic age. It took until 1963 for the most famous of these to get its name, EMP or electromagnetic pulse, which can destroy electronic equipment many miles away.
The term ground zero was coined in 1946 to denote the point of impact or point directly underneath a nuclear explosion. The term critical mass dates to 1941.
The dawn of the atomic age did leave us at least one less-grim term. The bikini was named in 1947, after the site of a 1946 atomic test in the Pacific.
