The mushroom cloud after an impact of the Tsar Bomb dropped (Credit: Science Photo Library) A hydrogen bomb, or a thermonuclear bomb, co...
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| The mushroom cloud after an impact of the Tsar Bomb dropped (Credit: Science Photo Library) |
A hydrogen bomb has never been used in battle by any country, but experts say it has the power to wipe out entire cities and kill significantly more people than the already powerful atomic bomb, which the U.S. dropped in Japan during World War II, killing tens of thousands of people.
As global tensions continue to rise over North Korea’s nuclear weapons program, here’s what to know about atomic and hydrogen bombs:
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| Characteristic mushroom shaped cloud begins formation after the first H-Bomb explosion (US) at Eniwetok Atoll in the Pacifi on 6th November 1952. Three Lions | Getty Images |
But a hydrogen bomb has the potential to be 1,000 times more powerful than an atomic bomb, according to several nuclear experts. The U.S. witnessed the magnitude of a hydrogen bomb when it tested one within the country in 1954. Hydrogen bombs cause a bigger explosion, which means the shock waves, blast, heat and radiation all have larger reach than an atomic bomb, according to Edward Morse, a professor of nuclear engineering at University of California, Berkeley.
Although no other country has used such a weapon of mass destruction since World War II, experts say it would be even more catastrophic if a hydrogen bomb were to be dropped instead of an atomic one.“With the [atomic] bomb we dropped in Nagasaki, it killed everybody within a mile radius,” Morse stated that a hydrogen bomb’s reach would be closer to 5 or 10 miles. “In other words, you kill more people,” he said.
Hall, director of the University of Tennessee’s Institute for Nuclear Security, called the hydrogen bomb a “city killer” that would probably annihilate between 100 and 1,000 times more people than an atomic bomb. “It will basically wipe out any of modern cities,” Hall said. “A regular atomic bomb would still be devastating, but it would not do nearly as much damage as an H-bomb.”
What’s the difference between hydrogen bombs and atomic bombs?
“The way the hydrogen bomb works — it’s really a combination of fission and fusion together,” said Eric Norman, who also teaches nuclear engineering at UC Berkeley. In both cases, a significant amount of energy is released, which drives the explosion, experts say. However, more energy is released during the fusion process, which causes a bigger blast. “The extra yield is going to give you more bang,” Morse said.
Morse said the atomic bombs dropped on Japan were each equivalent to just about 10,000 kilotons of TNT. “Those were the little guys,” Morse said. “Those were small bombs, and they were bad enough.” Hydrogen bombs, he said, would result in a yield of about 100,000 kilotons of TNT, up to several million kilotons of TNT, which would mean more deaths. Hydrogen bombs are also harder to produce but lighter in weight, meaning they could travel farther on top of a missile, according to experts.
What are the similarities between hydrogen bombs and atomic bombs?
Both bombs are extremely lethal and have the power to kill people within seconds, as well as hours later due to radiation. Blasts from both bombs would also instantly burn wood structures to the ground, topple big buildings and render roads unusable such devastation in an article published on March 11, 1946, on the aftermath of the atomic bombs dropped on Japan.
The piece read: “In the following waves [after the initial blast] people’s bodies were terribly squeezed, then their internal organs ruptured. Then the blast blew the broken bodies at 500 to 1,000 miles per hour through the flaming, rubble-filled air. Practically everybody within a radius of 6,500 feet was killed or seriously injured and all buildings crushed or disemboweled.”
Russian Tsar Bomb
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| This mock-up of Tsar Bomba show's the weapon's enormous size (Credit: Science Photo Library) |
The Tupolev’s pilot, Major Andrei Durnovtsev, brought the aircraft to Mityushikha Bay, a Soviet testing range, at a height of about 34,000ft (10km). A smaller, modified Tu-16 bomber flew beside, ready to film the ensuing blast and monitor air samples as it flew from the blast zone. In order to give the two planes a chance to survive – and this was calculated as no more than a 50% chance – Tsar Bomba was deployed by a giant parachute weighing nearly a tonne. The bomb would slowly drift down to a predetermined height – 13,000ft (3,940m) – and then detonate. By then, the two bombers would be nearly 50km (30 miles) away. It should be far enough away for them to survive.
On Novya Zemlya, the effects were catastrophic
Tsar Bomba detonated at 11:32, Moscow time. In a flash, the bomb created a fireball five miles wide. The fireball pulsed upwards from the force of its own shockwave. The flash could be seen from 1,000km (630 miles) away. The bomb’s mushroom cloud soared to 64km (40 miles) high, with its cap spreading outwards until it stretched nearly 100km (63 miles) from end to end. It must have been, from a very far distance perhaps, an awe-inspiring sight.
On Novaya Zemlya, the effects were catastrophic. In the village of Severny, some 55km (34 miles) from Ground Zero, all houses were completely destroyed (this is the equivalent to Gatwick airport being destroyed by a bomb that had fallen on Central London). In Soviet districts hundreds of miles from the blast zone, damage of all kinds – houses collapsing, roofs falling in, damage to doors, windows shattering – were reported. Radio communications were disrupted for more than an hour.
On Novaya Zemlya, the effects were catastrophic. In the village of Severny, some 55km (34 miles) from Ground Zero, all houses were completely destroyed (this is the equivalent to Gatwick airport being destroyed by a bomb that had fallen on Central London). In Soviet districts hundreds of miles from the blast zone, damage of all kinds – houses collapsing, roofs falling in, damage to doors, windows shattering – were reported. Radio communications were disrupted for more than an hour.
Durovtsev’s Tupolev was lucky to survive; the blast wave from Tsar Bomba caused the giant bomber to plummet more than 1,000m (3,300ft) before the pilot could regain control. One Soviet cameraman who witnessed the detonation said: “The clouds beneath the aircraft and in the distance were lit up by the powerful flash. The sea of light spread under the hatch and even clouds began to glow and became transparent. At that moment, our aircraft emerged from between two cloud layers and down below in the gap a huge bright orange ball was emerging.
The ball was powerful and arrogant like Jupiter. Slowly and silently it crept upwards... Having broken through the thick layer of clouds it kept growing. It seemed to suck the whole Earth into it. The spectacle was fantastic, unreal, supernatural.” Tsar Bomba unleashed almost unbelievable energy – now widely agreed to be in the order of 57 megatons, or 57 million tons of TNT. That is more than 1,500 times that of the Hiroshima and Nagasaki bombs combined, and 10 times more powerful than all the munitions expended during World War Two. Sensors registered the bomb’s blast wave orbiting the Earth not once, not twice, but three times.
The ball was powerful and arrogant like Jupiter. Slowly and silently it crept upwards... Having broken through the thick layer of clouds it kept growing. It seemed to suck the whole Earth into it. The spectacle was fantastic, unreal, supernatural.” Tsar Bomba unleashed almost unbelievable energy – now widely agreed to be in the order of 57 megatons, or 57 million tons of TNT. That is more than 1,500 times that of the Hiroshima and Nagasaki bombs combined, and 10 times more powerful than all the munitions expended during World War Two. Sensors registered the bomb’s blast wave orbiting the Earth not once, not twice, but three times.
Because the fireball had not made contact with the Earth, there was a surprisingly low amount of radiation.
Such a blast could not be kept secret. The US had a spyplane only tens of kilometres from the blast. It carried a special optical device called a bhangmeter useful for calculating the yield of far-off nuclear explosions. Data from this aircraft – codenamed Speedlight – was used by the Foreign Weapons Evaluation Panel to calculate this mystery test’s yield.
International condemnation soon followed, not only from the US and Britain, but from some of the USSR’s Scandinavian neighbours such as Sweden. The only silver lining in this mushroom cloud was that because the fireball had not made contact with the Earth, there was a surprisingly low amount of radiation. It could have been very different. But for a change in its design to rein in some of the power it could unleash, Tsar Bomba was supposed to have been twice as powerful.
One of the architects of this formidable device was a Soviet physicist called Andrei Sakharov – a man who would later become world famous for his attempts to rid the world of the very weapons he had helped create. He was a veteran of the Soviet atomic bomb programme from the very beginning, and had been part of the team that had built some of the USSR’s earliest atom bombs. Sakharov began work on a layered fission-fusion-fission device, a bomb that would create further energy from the nuclear processes in its core.
This involved wrapping deuterium – a stable isotope of hydrogen – with a layer of unenriched uranium. The uranium would capture neutrons from the igniting deuterium and would itself start to react. Sakharov called it the sloika, or layered cake. This breakthrough allowed the USSR to build its first hydrogen bomb, a device much more powerful than the atomic bombs of only a few years before. Sakharov had been told by Khrushchev to come up with a bomb that was more powerful than anything else tested so far.
International condemnation soon followed, not only from the US and Britain, but from some of the USSR’s Scandinavian neighbours such as Sweden. The only silver lining in this mushroom cloud was that because the fireball had not made contact with the Earth, there was a surprisingly low amount of radiation. It could have been very different. But for a change in its design to rein in some of the power it could unleash, Tsar Bomba was supposed to have been twice as powerful.
One of the architects of this formidable device was a Soviet physicist called Andrei Sakharov – a man who would later become world famous for his attempts to rid the world of the very weapons he had helped create. He was a veteran of the Soviet atomic bomb programme from the very beginning, and had been part of the team that had built some of the USSR’s earliest atom bombs. Sakharov began work on a layered fission-fusion-fission device, a bomb that would create further energy from the nuclear processes in its core.
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| Andrei Dmitrievich Sakharov Russian nuclear physicist (Credit: Science Photo Library) |
The Soviet Union needed to show that it could pull ahead of the US in the nuclear arms race, according to Philip Coyle, the former head of US nuclear weapons testing under President Bill Clinton, who spent 30 years helping design and test atomic weapons. “The US had been very far ahead because of the work it had done to prepare the bombs for Hiroshima and Nagasaki. And then it did a large number of tests in the atmosphere before the Russians even did one.
“We were ahead and the Soviets were trying to do something to tell the world that they were to be reckoned with. Tsar Bomba was primarily designed to cause the world to sit up and take notice of the Soviet Union as an equal,” says Coyle. The original design – a three layered bomb, with uranium layers separating each stage – would have had a yield of 100 megatons – 3,000 times the size of the Hiroshima and Nagasaki bombs.
That was of particular concern to Sakharov, says Frank von Hippel, a physicist and head of Public and International Affairs at Princeton University. “He was really apprehensive about the amount of radioactivity it would create,” he says, “and the genetic effects that could have on future generations
“It was the beginning of his journey from being a bomb designer to becoming a dissident.”
Before it was ready to be tested, the uranium layers that would have helped the bomb achieve its enormous yield were replaced with layers of lead, which lessened the intensity of the nuclear reaction.
The Soviets had built a weapon so powerful that they were unwilling to even test it at its full capacity. And that was only one of the problems with this devastating device. The Tu-95 bombers built to carry the Soviet Union’s nuclear weapons were designed to carry much lighter weapons. The Tsar Bomba was so big that it couldn’t be placed on a missile, and so heavy that the planes designed to carry it wouldn’t have been able to take them all the way to their targets with enough fuel. And, if the bomb was as powerful as intended, the aircraft would have been on a one-way mission anyway.
“We were ahead and the Soviets were trying to do something to tell the world that they were to be reckoned with. Tsar Bomba was primarily designed to cause the world to sit up and take notice of the Soviet Union as an equal,” says Coyle. The original design – a three layered bomb, with uranium layers separating each stage – would have had a yield of 100 megatons – 3,000 times the size of the Hiroshima and Nagasaki bombs.
It was the beginning of his journey from being a bomb designer to becoming a dissident – Frank von HippelThe Soviets had already tested large devices in the atmosphere, equivalent to several megatons, but this would have been far, far bigger. Some scientists began to believe it was too big. With such immense power, there would be no guarantee that the giant bomb wouldn’t swamp the north of the USSR with a vast cloud of radioactive fallout.
That was of particular concern to Sakharov, says Frank von Hippel, a physicist and head of Public and International Affairs at Princeton University. “He was really apprehensive about the amount of radioactivity it would create,” he says, “and the genetic effects that could have on future generations
“It was the beginning of his journey from being a bomb designer to becoming a dissident.”
Before it was ready to be tested, the uranium layers that would have helped the bomb achieve its enormous yield were replaced with layers of lead, which lessened the intensity of the nuclear reaction.
The Soviets had built a weapon so powerful that they were unwilling to even test it at its full capacity. And that was only one of the problems with this devastating device. The Tu-95 bombers built to carry the Soviet Union’s nuclear weapons were designed to carry much lighter weapons. The Tsar Bomba was so big that it couldn’t be placed on a missile, and so heavy that the planes designed to carry it wouldn’t have been able to take them all the way to their targets with enough fuel. And, if the bomb was as powerful as intended, the aircraft would have been on a one-way mission anyway.
Even where nuclear weapons are concerned, there can be such as thing as too powerful, says Coyle, who is now a leading member of the Center for Arms Control and Non-Proliferation, a think tank based in Washington DC. “It’s hard to find a use for it unless you want to knock down very large cities,” he says. “It simply would be too big to use.”
Von Hippel agrees. “These things [large free-falling nuclear bombs] were designed that if you wanted to be able to destroy the target even if you were a mile off, it could be done. Things moved in a different direction – increasing missile accuracy and multiple warheads.”
Von Hippel agrees. “These things [large free-falling nuclear bombs] were designed that if you wanted to be able to destroy the target even if you were a mile off, it could be done. Things moved in a different direction – increasing missile accuracy and multiple warheads.”
It’s hard to find a use for it unless you want to knock down very large cities – Philip Coyle
Tsar Bomba had other effects. Such was the concern over the test – which was 20% of the size of every atmospheric test combined before it, von Hippel says – that it hastened the end of atmospheric testing in 1963. Von Hippel says that Sakharov was particularly worried by the amount of radioactive carbon 14 that was being emitted into the atmosphere – an isotope with a particularly long half-life. “This has been partly mitigated by all the fossil fuel carbon in the atmosphere which has diluted it,” he says.
Sakharov worried that a bomb bigger than the one tested would not be repelled by its own blastwave – like Tsar Bomba had been – and would cause global fallout, spreading toxic dirt across the planet.
Sakharov become an ardent supporter of the 1963 Partial Test Ban, and an outspoken critic of nuclear proliferation and, in the late 1960s, anti-missile defences that he feared would spur another nuclear arms race. He became increasingly ostracised by the state, a dissident against oppression who would in 1975 be awarded the Nobel Peace Prize, and referred to as “the conscience of mankind”, says von Hippel.
Sakharov worried that a bomb bigger than the one tested would not be repelled by its own blastwave – like Tsar Bomba had been – and would cause global fallout, spreading toxic dirt across the planet.
Sakharov become an ardent supporter of the 1963 Partial Test Ban, and an outspoken critic of nuclear proliferation and, in the late 1960s, anti-missile defences that he feared would spur another nuclear arms race. He became increasingly ostracised by the state, a dissident against oppression who would in 1975 be awarded the Nobel Peace Prize, and referred to as “the conscience of mankind”, says von Hippel.