Nuclear — fission · USSR · 1949
RDS-1
RDS-1 (“First Lightning”, Joe-1)
The first Soviet nuclear test. Its design was very close to Fat Man’s, partly thanks to espionage.
See RDS-1 in the 3D simulator- Yield
- 22 ktDocumented
- Energy
- 92 TJ
- Type
- First Soviet test (plutonium, implosion)
- Period
- Cold War
- Status
- Single test
RDS-1 releases about 1.5 times the energy of Little Boy (Hiroshima, 1945).
Key points
- Detected by American surveillance aircraft thanks to radioactive particles in the atmosphere.
History
The test ended the American nuclear monopoly only four years after Hiroshima and launched the Cold War arms race.
- 1943 The Soviet nuclear program begins.
- 29 August 1949 RDS-1 test at Semipalatinsk.
- September 1949 The United States announces it has detected the test.
How does it work?
A fission weapon releases energy by splitting heavy nuclei (uranium-235 or plutonium-239). Each fission releases about 200 MeV and a few neutrons.
If these neutrons cause further fissions, a chain reaction runs away in less than a millionth of a second.
The energy heats matter to tens of millions of degrees: fireball, thermal radiation and shock wave.
General principle of implosion: conventional explosives strongly compress the fissile material, which becomes “supercritical” and sustains the chain reaction.
Deliberately general explanations: the application provides no design or manufacturing information.
Frequently asked questions
How powerful is RDS-1?
RDS-1 has an estimated yield of 22 kt of TNT equivalent, about 92 TJ of energy.
What is the history of RDS-1?
Single test, on 29 August 1949, at the Semipalatinsk test site (Kazakhstan). The test ended the American nuclear monopoly only four years after Hiroshima and launched the Cold War arms race.
What does the RDS-1 explosion look like?
The Bomb Simulator shows the fireball, shock wave and cloud of RDS-1 at real scale, over Paris, London or New York, with the sources and reliability of each value.
Sources
- RDS-1 — Wikipedia (overview, to be cross-checked)
Other weapons
- Trinity — 25 kt
- Little Boy — 15 kt
- Fat Man — 21 kt
- Hurricane — 25 kt
- RDS-6s — 400 kt
- Gerboise Bleue — 70 kt
- 596 — 22 kt
- Davy Crockett — 20 t
- Ivy Mike — 10.4 Mt
- 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.