The Nuclear Age - History of Science

Discovering the Atom (1895-1932)

Wilhelm Rontgen discovered X-rays in 1895. Henri Becquerel discovered radioactivity in 1896 by accident (uranium fogged a photographic plate). Marie and Pierre Curie isolated radium and polonium, with Marie winning two Nobel Prizes. Ernest Rutherford's gold foil experiment (1911) proved the atom had a tiny, dense nucleus. James Chadwick discovered the neutron in 1932, completing the basic model of the atom.

Fission Discovery (1938)

Otto Hahn and Fritz Strassmann in Berlin bombarded uranium with neutrons and found barium in the products - the atom had split. Lise Meitner and Otto Frisch (working in exile from Nazi Germany) provided the theoretical explanation: nuclear fission. Frisch's calculation showed the energy released was enormous - matching Einstein's E=mc2. The news reached physicists worldwide in weeks and the implications were immediately obvious.

The Manhattan Project (1942-1945)

Fearing Nazi Germany was developing nuclear weapons, Albert Einstein and Leo Szilard wrote to President Roosevelt. The result was the Manhattan Project - the largest scientific mobilization in history. 130,000 people worked across 30 sites in the USA, UK, and Canada. Three factories were built in secret: Oak Ridge (uranium enrichment), Hanford (plutonium production), Los Alamos (bomb design). Total cost: $2 billion (about $28 billion today).

Trinity and Hiroshima (1945)

The first nuclear test, "Trinity," detonated July 16, 1945 in New Mexico. Oppenheimer recalled a line from the Bhagavad Gita: "Now I am become Death, the destroyer of worlds." Three weeks later Little Boy (uranium bomb) destroyed Hiroshima on August 6, killing 80,000 instantly. Fat Man (plutonium bomb) destroyed Nagasaki on August 9, killing 40,000 instantly. Japan surrendered on August 15. Total deaths including radiation effects: 129,000-226,000.

The Cold War Arms Race

The USSR tested its first bomb in 1949, ending the US monopoly. The US tested a hydrogen bomb (1952, 10 megatons - 500x Hiroshima). The USSR followed in 1953. By 1986 the global arsenal peaked at 70,000 warheads. Multiple near-misses came terrifyingly close to accidental nuclear war: the 1962 Cuban Missile Crisis, the 1983 Able Archer NATO exercise, and Stanislav Petrov's decision in 1983 not to report a false Soviet early warning alert.

Civilian Nuclear Power

The first nuclear power plant to produce electricity was EBR-1 in Idaho in 1951. The first commercial plant, Calder Hall in the UK, opened in 1956. Nuclear power expanded rapidly in the 1960s-70s. At its peak it provided 17% of global electricity. Three Mile Island (1979), Chernobyl (1986), and Fukushima (2011) caused major setbacks. A new wave of nuclear construction is now underway, driven by climate concerns.