What if a Nuclear Bomb Hit Buenos Aires?

Argentina · Population 3,075,000 · Density 14,500/km²

About Buenos Aires

The capital of Argentina and second-largest metropolitan area in South America.

Below are four scenario calculations using historical and modern nuclear weapons. Each row shows the radius of an effect zone in kilometers and a rough order-of-magnitude estimate of people inside that zone, derived from the city's urban population density. Numbers are educational approximations — see the methodology page for the underlying formulas.

Little Boy on Buenos Aires (15 kt)

USA · 1945 · Hiroshima bomb

Effect zoneRadiusEst. affected
Fireball (vaporization, 100% fatal)0.43 km~8,358
Severe blast (20 PSI, ~98% fatal)1.18 km~53,594
Moderate blast (5 PSI, ~50% fatal)2.52 km~112,731
Light blast (1 PSI, glass injuries)7.16 km~102,366
3rd-degree thermal burns2.03 km

W76 on Buenos Aires (100 kt)

USA · 1978 · Common SLBM warhead

Effect zoneRadiusEst. affected
Fireball (vaporization, 100% fatal)0.91 km~38,129
Severe blast (20 PSI, ~98% fatal)2.20 km~178,561
Moderate blast (5 PSI, ~50% fatal)4.71 km~394,294
Light blast (1 PSI, glass injuries)13.39 km~358,044
3rd-degree thermal burns4.43 km

Castle Bravo on Buenos Aires (15 Mt)

USA · 1954 · Most powerful US nuclear test

Effect zoneRadiusEst. affected
Fireball (vaporization, 100% fatal)6.79 km~2,099,553
Severe blast (20 PSI, ~98% fatal)11.51 km~3,816,857
Moderate blast (5 PSI, ~50% fatal)24.60 km~10,765,655
Light blast (1 PSI, glass injuries)69.98 km~9,775,903
3rd-degree thermal burns34.54 km

Tsar Bomba on Buenos Aires (50 Mt)

USSR · 1961 · Largest nuclear weapon ever tested

Effect zoneRadiusEst. affected
Fireball (vaporization, 100% fatal)10.99 km~5,500,851
Severe blast (20 PSI, ~98% fatal)17.13 km~7,595,739
Moderate blast (5 PSI, ~50% fatal)36.60 km~23,830,899
Light blast (1 PSI, glass injuries)104.12 km~21,639,981
3rd-degree thermal burns56.58 km

Limitations

These estimates assume an idealized air burst over the city center, uniform population density, and no advance warning or sheltering. Real-world casualties would depend on:

  • Time of day (population is concentrated downtown during business hours)
  • Sheltering and basements (subway systems can reduce casualties significantly)
  • Building construction (reinforced steel/concrete vs. wood-frame)
  • Weather and atmospheric conditions
  • Detonation altitude (air burst vs. surface burst)
  • Subsequent fallout and infrastructure collapse

Other City Scenarios

FAQ

What would happen if a nuclear bomb hit Buenos Aires?

Buenos Aires has approximately 3,075,000 people and an urban density around 14,500 per km². A Hiroshima-yield warhead (15 kt Little Boy) detonated over Buenos Aires would produce a moderate blast radius of about 2.5 km, with an estimated 61,952 immediate fatalities in the severe-blast zone. A modern strategic warhead (W76, 100 kt) would extend the moderate-damage zone to roughly 4.7 km with thermal burns reaching 4.4 km. Run the interactive simulator above to see the exact zones overlaid on the map.

How many people would die in Buenos Aires from a nuclear strike?

A 100 kt W76 strategic warhead air-burst over Buenos Aires could cause an estimated 610,984 immediate fatalities and around 358,044 additional injured. For comparison, a 50 Mt Tsar Bomba — the largest weapon ever tested — would put roughly 493,825,280 people inside the 1 PSI light-blast zone alone. Real casualties depend strongly on time of day, sheltering, weather, and altitude of detonation.

What is the blast radius of a nuclear bomb over Buenos Aires?

For a 100 kt strategic warhead over Buenos Aires: fireball radius 0.91 km, severe blast (20 PSI) 2.20 km, moderate blast (5 PSI) 4.71 km, light blast (1 PSI) 13.39 km, third-degree thermal burns 4.43 km. Larger yields scale these radii roughly as the cube root of yield for blast and the 0.41 power for thermal effects.

Is Buenos Aires a likely nuclear target?

This is an educational simulator and does not assess threat probability. Buenos Aires is one of the world's most prominent cities in South America, which is why we feature it as a scenario. The purpose of these visualizations is to convey the humanitarian scale of nuclear weapons — not to make any operational claim.

See also: full Weapons Database (45+ entries) · Scientific methodology · Data sources.