Thermonuclear · United States · 1952
Ivy Mike
Ivy Mike test (“Sausage”)
The first large-scale demonstration of thermonuclear fusion. The device, cooled with liquid hydrogen, could not be transported.
See Ivy Mike in the 3D simulator- Yield
- 10.4 MtDocumented
- Energy
- 43.5 PJ
- Type
- First two-stage thermonuclear device (experimental)
- Period
- Cold War
- Status
- Single test
Ivy Mike releases about 690 times the energy of Little Boy (Hiroshima, 1945).
Key points
- The islet of Elugelab was wiped off the map: a crater 1.9 km wide and 50 m deep.
- The cloud reached 17 km in 90 s, then stabilized at around 41 km altitude; its top eventually spread over ~160 km.
- Device of about 49 t (74 t with its cryogenic equipment).
History
Carried out a few weeks before the end of Truman’s term, the test opened the megaton era. The USSR tested its first two-stage device three years later.
- 1951 Teller–Ulam principle of two-stage staging.
- 1 November 1952 Ivy Mike test at Enewetak.
- 1954 First transportable thermonuclear weapons (Castle series).
How does it work?
A thermonuclear weapon (“H-bomb”) first uses a fission explosion, which creates the extreme conditions needed to fuse light nuclei (hydrogen isotopes).
Fusion releases a lot of energy per unit of mass and is not limited by a critical mass: this is what makes the megaton range and beyond possible.
One megaton (Mt) is the energy of one million tons of TNT, about 4.2 × 10¹⁵ joules.
Deliberately general explanations: the application provides no design or manufacturing information.
Frequently asked questions
How powerful is Ivy Mike?
Ivy Mike has an estimated yield of 10.4 Mt of TNT equivalent, about 43.5 PJ of energy.
What is the history of Ivy Mike?
Single test, on 1 November 1952, in the Marshall Islands. Carried out a few weeks before the end of Truman’s term, the test opened the megaton era. The USSR tested its first two-stage device three years later.
What does the Ivy Mike explosion look like?
The Bomb Simulator shows the fireball, shock wave and cloud of Ivy Mike at real scale, over Paris, London or New York, with the sources and reliability of each value.
Sources
- Ivy Mike — Wikipedia (overview, to be cross-checked)
- The Effects of Nuclear Weapons, 3rd ed. (Glasstone & Dolan, 1977) — U.S. DoD / DOE (OSTI)
Other weapons
- Trinity — 25 kt
- Little Boy — 15 kt
- Fat Man — 21 kt
- RDS-1 — 22 kt
- Hurricane — 25 kt
- RDS-6s — 400 kt
- Gerboise Bleue — 70 kt
- 596 — 22 kt
- Davy Crockett — 20 t
- Castle Bravo — 15 Mt
- RDS-37 — 1.6 Mt
- Mk 17 — 15 Mt
This application is an educational tool. The animations and effect zones are simplified representations meant to illustrate orders of magnitude. They are neither a prediction of the effects of a real weapon nor a military planning tool.