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|Soviet Atomic Bomb Project|
The fathers of the Soviet nuclear program, Dr. Andrei Sakharov (left) with Dr. Igor Kurchatov (right).
|Active||1943 - 1949|
|Part of||Ministry of Medium Machine Building|
|Garrison/HQ||Atomgrad, Soviet Union
Semipalatinsk Test Site
The Soviet project to develop an atomic bomb (Russian: Создание советской атомной бомбы) was a clandestine research and development program begun during and post-World War II, in the wake of the Soviet Union's discovery of the United States' nuclear project. This scientific research was directed by Soviet nuclear physicist Igor Kurchatov, while the military logistics and intelligence efforts were undertaken and managed by NKVD director Lavrentiy Beria. The Soviet Union benefited from highly successful espionage efforts on the part of the Soviet military intelligence (GRU). During the midst of World War II, the program was started by Joseph Stalin who received a letter from physicist Georgy Flyorov urging him to start the research, as Flyorov had long suspected that many of the Allied powers were already secretly advancing after the discovery of nuclear fission in 1939. However, because of the bloody and intensified war with Germany on the Eastern Front, the large scale efforts prevented Soviets from developing the atomic bomb, but accelerated the program after the American atomic bombings of Hiroshima and Nagasaki, thus putting an end to World War II. The Soviet atomic project was charged with gathering intelligence efforts on German nuclear program as well as the American nuclear efforts. After the atomic raids on Japan and the subsequent Japanese surrender in 1945, the Soviet Union expanded its research facilities, military reactors, and employed a number of scientists, including its atomic spies who successfully penetrated the American nuclear weapons efforts.
Through its successful Russian Alsos and the atomic spy ring, the Soviet Union's espionage ultimately led them to conduct the first test of its implosion-type nuclear device, codename First Lightning on 29 August 1949, at Semipalatinsk, Kazakh SSR. With the success of this test, the Soviet Union became the second nation after the United States to have successfully developed and conducted nuclear tests.
In early 1930s, the Soviets were the instrumental contributors made to the advancement of nuclear physics and its related sciences, such as nuclear chemistry. The initial Soviet interest in nuclear physics had begun in the early 1930s through the Soviet Academy of Sciences, an era in which a variety of important nuclear discoveries and achievements were made (the identification of the neutron and proton as fundamental particles, the operation of the first cyclotron to energies of over 1 MeV, and the first "splitting" of the atomic nucleus by John Cockcroft and Ernest Walton). Even before the Russian revolution and the followed by the February Revolution, the mineralogist Vladimir Vernadsky had made a number of public calls for a survey of Soviet Union's uranium deposits. The main motivation for nuclear research at the time was radium, which had scientific as well as medical uses, and could be retrieved from borehole water from the Ukhta oilfields.
After the discovery of nuclear fission in the late 1930s, scientists in the Soviet Union, like scientists all over the world, realized that nuclear reactions could, in theory, be used to release large amounts of binding energy from the atomic nucleus of uranium. As in the West, the news of fission created great excitement amongst Soviet scientists and many physicists switched their lines of research to those involving nuclear physics in particular, as it was considered a promising field of research. Few scientists thought it would be possible to harness the power of nuclear energy for human purposes within the span of many decades. Soviet nuclear research was not far behind Western scientists: Yakov Frenkel did the first theoretical work on fission in the Soviet Union in 1940, and Georgii Flerov and Lev Rusinov concluded that 3±1 neutrons were emitted per fission only days after similar conclusions had been reached by the team of Frédéric Joliot-Curie.
Soviet physicist Georgy Flyorov noticed that in spite of the progress German, British and American physicists had made in research into uranium fission, scientific journals had ceased publishing papers on the topic. Flyorov deduced that this meant such research had been classified in the countries concerned, and wrote to Stalin in April 1942. He cited the lack of response he had himself encountered trying to generate interest in similar research, and warned Stalin of the consequences of the development of atomic weapons: "...the results will be so overriding [that] it won't be necessary to determine who is to blame for the fact that this work has been neglected in our country". By September 1942, Stalin, who had already been presented with evidence of the Western nuclear programs, decided to launch a Soviet program to develop an atomic bomb headed by Igor Kurchatov.
In the wake of the atomic bombing of the Japanese cities of Hiroshima and Nagasaki and Japan's surrender, Stalin took the decision to accelerate research and development, expanding the development military nuclear reactors and research facilities all over the country.
Initially in 1940, the administration of this program was given to the Soviet Ministry of Foreign Affairs with Foreign Minister Vyacheslav Molotov as being its first administrator. Stalin and Molotov tasked the USSR Academy of Sciences to find a science administrator notable for leading the research in nuclear physics. Abram Fedorovich Ioffe recommended Igor Kurchatov to Molotov, and Molotov advised Stalin to appoint Kurchatov as the formal scientific head of the nascent Soviet nuclear weapons programme. Other important figures included Yuli Khariton, Yakov Zeldovich, Georgii Flyorov, Abram Fedorovich Ioffe, and the future dissident and lead theoretical designer of the hydrogen bomb, Andrei Sakharov.
But, by the 1944, the Soviet Foreign Affairs Ministry and Foreign Minister Molotov as well proved to be an incapable and politically weak administrator for running this large magnitude project. Soon, the program suffered a major setback under Molotov who lost the focus of this program because of the war with Germany. In 1944, Stalin handed over the program to People's Commissariat for Internal Affairs (NKVD) and Molotov was replaced by ruthless Lavrentii Beria, Chief of NKVD, in 1944. As ruthless and dangerous as Beria was, the NKVD aided atomic spies operated under the administrative ring, directly reported to Beria. Beria also infiltrated and ruthlessly penetrated the German nuclear program, with many notable figures in German nuclear program were forcefully taken to Soviet Union where the German figures greatly enhanced the Soviet nuclear weapons efforts.
The Soviet atomic project benefited from highly successful espionage efforts on the part of the Glavnoye Razvedyvatel'noye Upravleniye (GRU) as well as the foreign intelligence department of the Narodnyy komissariat vnutrennikh del (NKVD). Evidence from intelligence sources in the United Kingdom had a role to play in the decision of the Soviet State Defense Council (Gosudarstvennyj komitet oborony (GKO)), in September 1942, to approve resolution 2352, which signaled the beginning of the Soviet atom bomb project.
Through sources in the Manhattan Project, notably Klaus Fuchs, the Soviet intelligence obtained important information on the progress of the United States atomic bomb effort. Intelligence reports were shown to the head of the Soviet atomic project director Igor Kurchatov and had a significant impact on the direction of his own team's research.
For example, Soviet work on methods of uranium isotope separation was altered when it transpired, to Kurchatov's surprise, that the Americans had opted for the Gaseous diffusion method. Whilst research on other separation methods continued throughout the war years, the emphasis was placed on replicating U.S. success with gaseous diffusion. Another important breakthrough, attributed to intelligence, was the possibility of using plutonium, instead of uranium, in a fission weapon. Extraction of plutonium in the so-called "uranium pile" allowed the bypass of the difficult process of uranium separation altogether — something that Kurchatov had learned from intelligence from the Manhattan project.
In 1945, the Soviet intelligence obtained rough "blueprints" of the first U.S. atomic device, which may have contributed to the Soviet bomb project. Scholar Alexei Kojevnikov has estimated, based on newly released Soviet documents, that the primary way in which the espionage may have sped up the Soviet project was that it allowed Khariton to avoid dangerous tests to determine the size of the critical mass: "tickling the dragon's tail", as it was called in the U.S., consumed a good deal of time and claimed at least two lives; see Harry K. Daghlian, Jr. and Louis Slotin.
One of the key pieces of information, which Soviet intelligence obtained from Fuchs, was a cross-section for D-T fusion. This data was available to top Soviet officials roughly three years before it was openly published in the Physical Review in 1949. However, this data was not forwarded to Vitaly Ginzburg or Andrei Sakharov until very late, practically months before publication. Initially both Ginzburg and Sakharov, while working on the Sloika design, estimated such a cross-section to be similar to the D-D reaction. Once the actual cross-section become known to Ginzburg and Sakharov, the Sloika design become a priority, which resulted in successful test in 1953.
In the 1990s, with the declassification of Soviet intelligence materials, which showed the extent and the type of the information obtained by the Soviets from US sources, a heated debate ensued in Russia and abroad as to the relative importance of espionage, as opposed to the Soviet scientists' own efforts, in the making of the Soviet bomb. The vast majority of scholars agree that whereas the Soviet atomic project was first and foremost a product of local expertise and scientific talent, it is clear that espionage efforts contributed to the project in various ways and most certainly shortened the time needed to develop the atomic bomb.
Comparing the timelines of H-bomb development, some researchers came to a conclusion that Soviets had a gap in access to classified information regarding the H-bomb at least between late 1950 and some time in 1953. Earlier, e.g. in 1948, Fuchs gave to the Soviets a detailed update of the classical super progress, including an idea to use lithium, but did not specify it was specifically lithium-6. Teller accepted the fact that "classical super" scheme was infeasible by 1951, following results obtained by various researches (including Stanislaw Ulam) and calculations performed by John von Neumann in late 1950.
Yet the research for the Soviet analogue of "classical super" continued until December 1953, when the researchers were reallocated to a new project working on what later became a true H-bomb design, based on radiation implosion. It remains an open topic for research, whether the Soviet intelligence was able to obtain any specific data on Teller-Ulam design in 1953 or early 1954. Yet, Soviet officials directed the scientists to work on a new scheme, and the entire process took less than two years, commencing around January 1954 and producing a successful test in November 1955. It also took just several months before the idea of radiation implosion was conceived, and there is no documented evidence claiming priority. It is also possible that Soviets were able to obtain a document lost by John Wheeler on a train in 1953, which reportedly contained key information about thermonuclear weapon design.
The single largest problem during the early Soviet project was the procurement of uranium ore, as the USSR had no known domestic sources at the beginning of the project. The Soviet F-1 reactor, which began operation in December 1946, was fueled using uranium confiscated from the remains of the German atomic bomb project. This uranium had been mined in the Belgian Congo, and had fallen into the hands of the Germans after their invasion and occupation of Belgium in 1940. Further sources of uranium in the early years of the program were mines in East Germany (SAG Wismut), Czechoslovakia, Bulgaria, Romania (near Stei) and Poland. Eventually large domestic sources were discovered.
The uranium for the Soviet nuclear weapons program came from the following countries in the years 1945 to 1950 (mine production only):
RDS-1, the first Soviet atomic test was internally code-named First Lightning (Первая молния, or Pervaya Molniya) August 29, 1949, and was code-named by the Americans as Joe 1. The design was very similar to the first US "Fat Man" plutonium bomb, using a TNT/hexogen implosion lens design.
On September 24, 1951, the 38.3 kiloton device RDS-2 was tested based on a tritium "boosted" uranium implosion device (not a shot-gun design like the US "Little Boy" bomb) with a levitated core. This test was code named Joe-2 by American analysts.
On October 18, 1951, the 41.2 kiloton device RDS-3 was detonated, a boosted weapon using a composite construction of levitated plutonium core and a uranium-235 shell. Code named Joe-3 in the USA, this was the first Soviet air-dropped bomb test. Released at an altitude of 10 km, it detonated 400 meters above the ground.
RDS-4 represented a branch of research on small tactical weapons. It was a boosted fission device using plutonium in a "levitated" core design. The first test was an air drop on August 23, 1953, yielding 28 kilotons. The RDS-4 comprised the warhead of the R-5M medium-range ballistic missile, which was tested with a live warhead for the first and only time on February 2, 1956. The RDS-5 was a similar levitated core design but with a composite plutonium core and uranium 235 shell.
RDS-6, the first Soviet test of a hydrogen bomb, took place on August 12, 1953 and was nicknamed Joe 4 by the Americans. It used a layer-cake design of fission and fusion fuels (uranium 235 and lithium-6 deuteride) and produced a yield of 400 kilotons, mostly from neutron-initiated fission rather than fusion.
A much lower-power version of the RDS-4 with a 3-10 kiloton yield, the RDS-9 was developed for the T-5 nuclear torpedo. A 3.5 kiloton underwater test was performed with the torpedo on September 21, 1955.
The first Soviet test of a "true" hydrogen bomb in the megaton range was conducted on November 22, 1955. It was dubbed RDS-37 by the Soviets. It was of the multi-staged, radiation implosion thermonuclear design called Sakharov's "Third Idea" in the USSR and the Teller-Ulam design in the USA,
The Tsar Bomba (Царь-бомба) was the largest, most powerful nuclear weapon ever detonated. It was a three-stage hydrogen bomb with a yield of about 50 megatons. This is equivalent to ten times the amount of all the explosives used in World War II combined. It was detonated on October 30, 1961, in the Novaya Zemlya archipelago, and was capable of approximately 100 megatons, but was purposely reduced shortly before the launch. Although weaponized, it was not entered into service; it was simply a demonstrative testing on the capabilities of the Soviet Union's military technology at that time. The explosion was hot enough to induce third degree burns at 100 km distance.
Chagan was a shot in the Nuclear Explosions for the National Economy or Project 7, the Soviet equivalent of the US Operation Plowshare to investigate peaceful uses of nuclear weapons. It was a subsurface detonation, and was fired on January 15, 1965. The site was a dry bed of the Chagan River at the edge of the Semipalatinsk Test Site, and was chosen such that the lip of the crater would dam the river during its high spring flow. The resultant crater had a diameter of 408 meters and was 100 meters deep. A major lake (10,000,000 m³) soon formed behind the 20–35 m high upraised lip, known as Chagan Lake or Balapan Lake.
The photo is sometimes confused with RDS-1 in literature.
During the Cold War the Soviet Union created at least ten closed cities, known as Atomgrads, in which nuclear weapons-related research and development took place. After the dissolution of the Soviet Union, all of the cities changed their names (most of the original code-names were simply the oblast and a number). All are still legally "closed", though some have parts of them accessible to foreign visitors with special permits (Sarov, Snezhinsk, and Zheleznogorsk).
|Cold War name||Current name||Established||Primary function(s)|
|Arzamas-16||Sarov||1946||Weapons design and research, warhead assembly|
|Chelyabinsk-40 and later 65||Ozyorsk||1947||Plutonium production, component manufacturing|
|Sverdlovsk-45||Lesnoy||1947||Uranium enrichment, warhead assembly|
|Tomsk-7||Seversk||1949||Uranium enrichment, component manufacturing|
|Chelyabinsk-70||Snezhinsk||1957||Weapons design and research|