This page shows a simulation of the 100000 kt nuclear bomb (100000 kt) detonated over London, England. The map displays the estimated fireball, the zones of heavy, moderate and light blast damage, thermal radiation and ionizing radiation. Click «What does that mean?» for a detailed legend, or run your own detonation on the main page.
100 megatons was the design yield of the Soviet AN602 — the Tsar Bomba — before its final stage was throttled back to 50 for the 1961 test. No weapon of this size was ever deployed: the bomb weighed 27 tonnes, no missile could lift it, and the arms race moved towards many smaller warheads instead. This scenario is therefore a physical ceiling, not a military one. The rings are enormous: a fireball about 12 km across, total destruction (20 psi) to roughly 13 km, collapse of houses (5 psi) to about 32 km, third-degree burns on exposed skin to about 75 km in clear weather, and broken windows (1 psi) out to about 100 km.
What that means in London
Centred on Westminster, the 13 km zone of total destruction covers all of Inner London — the City, Canary Wharf, Hampstead, Croydon's approaches, Wembley and Greenwich. The 32 km collapse ring reaches the whole of Greater London and beyond the M25 to Watford, Heathrow, Dartford and Epsom — more than 9 million people. Burns to 75 km extend to Reading, Luton, Guildford, Southend-on-Sea, Brighton's outskirts, Gatwick and Stansted; the 100 km ring of broken windows reaches Oxford, Cambridge, Brighton, Canterbury and Northampton — roughly a third of the population of England lives inside it. The 800-kiloton scenario shows what one real warhead does to the same city.
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