RDS-6s is the codename for a hydrogen bomb the Soviet Union detonated on August 12, 1953. The bomb detonation was done as a test at the Semipalatinsk test site, which is current day Northern Kazakhstan. The bomb detonated a force measured at 400 kilotons (400,000 tons) of TNT.

“Work on the super-bomb had begun in 1946, three years before the Soviet Union exploded its first atomic bomb. The project was organized by the First Chief Directorate under Lavrentii Beria, Minister of State Security (MGB)” (Siegelbaum). Igor Kurchatov, a physicist who had been appointed scientific director of the Soviet Union’s nuclear project in 1943, headed the program. “The design for the bomb was based on the ‘layer cake’ concept developed by the physicist Andrei Sakharov (1921-89), according to which alternate layers of thermonuclear material and uranium-238 were placed in a fission bomb” (Siegelbaum).

But the test was done in reaction to US bomb development, “RDS-6 was part of the Soviet Union’s efforts to catch up with the United States, which had detonated its first thermonuclear device with the ‘George’ test two years earlier in May 1951” (ctbto.org). Developing a strong nuclear arms program was crucial to Stalin. The world was advancing, and Stalin wanted the Soviet Union to be a powerful factor amongst world powers, and developing such devastating weapons would give the country that legitimacy. Even after Stalin’s death, the nuclear program continued to advance. The Soviets even used the RDS-6s detonation as leverage against the US, claiming they (the Soviets) not only had a hydrogen bomb, but that they had the capability of deploying it by air.

There were political setbacks for the Soviets, however, with the testing of this hydrogen bomb, “In a speech on March 1954, Georgii Malenkov, chairman of the Council of Ministers, referred to the danger of ‘a new world war, which with modern weapons means the end of world civilization.’ Raising this specter went beyond what Khrushchev and other party leaders were willing to acknowledge publicly, and even though he subsequently reverted to the standard line that nuclear aggression by the United States would lead to the ‘collapse of the capitalist social system,’ Malenkov could not undo the damage to his own political career” (Siegelbaum).

Throughout this time period both the US and the Soviet sought to advance their nuclear programs, and both had catastrophic consequences for surrounding populations, “The largest [test ever carried out by the US], Castle Bravo, yielded 15 megatons and created the worst radiological disaster in U.S. history. Several of the Marshall Islands’ atolls, including one where U.S. servicemen were stationed, were blanketed with fallout. The Japanese fishing vessel ‘Lucky Dragon Number 5’ was also heavily contaminated, causing the death of at least one crewman. This incident created an international uproar and a diplomatic crisis with Japan. One year later, the Soviet Union drew level with its own ‘true’ two-stage hydrogen bomb, codenamed RDS-37. A total of over 2,000 nuclear tests worldwide were conducted at the Semipalatinsk Test Site in modern-day Kazakhstan. More than a million residents were exposed to radiation. The region has reported a surge in cancer rates and birth defects” (ctbto.org).


Hydrogen Bomb




6 thoughts on “RDS-6s

  1. It is crazy just how many nuclear tests were done. That site must have been obliterated to have seen over 2,000 nuclear tests done in that one location. That amount of radiation is unfathomable to me.

  2. I really enjoyed this post and I particularly liked the focus on the the impact on nuclear tests. We always think about nuclear weapons in terms of them being used in warfare, but we rarely think about the millions of people who have been affected by nuclear weapons tests.

  3. I’ve always found the nuclear arms race to be particularly interesting. Just think, a little over seven years later, the Soviets were able to detonate the worlds largest nuclear weapon, the Tsar Bomba. These weapons were extremely dangerous, and I think we sometimes fail to realize how close the world was to a nuclear war.

  4. I loved the video. Nuclear weapons were a key point of contention between the US and Soviet Union, and in the aftermath of WWII left the Soviets without one. The early Cold War was almost characterized by the race for the biggest, and “baddest” bomb as a show of force.

  5. This post exploring the testing of H-bombs also illustrates how the Cold War sprread beyond the boundaries of the two protagonists (US and USSR) and the European flashpoints that drew most attention. The populations of Kazakhstan and the Marshall Island became participants in the Cold War in part because their regions were used for nuclear testing. Although these weapons were never used, their effects were long-lasting during and after the Cold War.

Leave a Reply

Your email address will not be published. Required fields are marked *