“I have become death, the destroyer of worlds”
From a passage in Hindu scripture, the Bhagavad Gita
Those words were quoted by one of the 20th century’s most brilliant, most productive, most controversial physicists, the eminent J. Robert Oppenheimer in the television documentary The Decision to Drop the Bomb. Oppenheimer is one of a number of individuals who are referred to as “the father of the atomic bomb” for his collaboration and leadership in the Manhattan project. He was a major proponent of and contributor to the development of atomic weapons and, in the end, realizing the terrible power he had helped to unlock, became a vocal opponent of their development.
In an as yet confirmed claim, North Korea reports that they have successfully completed a subterranean Hydrogen bomb test. If it is true, it is quite alarming; if it turns out to be untrue, which evidence seems to suggest, then it can be written off as just another publicity stunt by the childish, ever petulant Kim Jong-un and his obsessive desire to gain attention.
One may wonder about the relevance of this topic to astronomy and a blog devoted to the beauty and grandeur of the universe, something that would seem to be the diametric antithesis to the subject. Well, as it turns out, this topic or the generation of energy through nuclear means in general has much to do with astronomy, a link that is developed in detail in a recent article describing the addition of 4 new synthetic elements to the Periodic Table. In that article, I discuss nuclear fusion, the energy source that powers the stars:
All stars derive their energy through nuclear fusion, the transmutation of four hydrogen nuclei (protons) into a helium nucleus. For lower-mass stars like our sun, after all but 12% of the star’s core hydrogen has been depleted, during the star’s helium burning phase, the process will continue through a series of core contractions, heating and expansions, with the transmutation of 3 helium nuclei to form a Carbon-12 nucleus. This process, by which the transmutation of helium into carbon occurs, is known as the Triple-Alpha process, a 2-step nuclear fusion process that ultimately combines 3 He4 nuclei (alpha particles) to form a stable Carbon-12 nucleus; this is the only way carbon is produced and is the nuclear dead-end for solar class stars.
In that article, I go on to describe how heavy metals and the remainder of the Periodic Table above Iron, Cobalt and Nickel are produced, something that speaks to the awesome potential contained even in one gram of Uranium (two million grams of oil or three million grams of coal have the same potential power yield as contained in one gram of Uranium).
Two Types of Nuclear Processes
The splitting (or fission) of a heavier nucleus (ex. Uranium or Plutonium) into lighter, daughter nuclei (Barium, Strontium, Cesium, etc) and, in the process, the release of the binding energy that held the heavier nuclei together. This energy, the energy that bound the nucleus together, had its origins in the immediate aftermath of a supernova! Whether this energy is used for peaceful purposes in the generation of clean, carbon-free energy to power our modern civilization or as the most terrible weapon ever invented by the mind of man, it had it’s origins in the terrible beauty of a supernova! To unleash this power as a weapon, the power of a supernova, on a human population is evil in its purest, most extreme, most deranged form.
The synthesis of heavier nuclei by the combination of lighter nuclei. This is the energy source that powers the sunand all stars andis described in detail in my recent article describing the addition of 4 new synthetic elements to the Periodic Table. The Proton-Proton chain is the principal reaction that powers the sun and solar-class stars and consists of 3 steps where 4 protons are ultimately combined to form a He4 nucleus. The mass loss in this process (the mass of the He4 nucleus is less than the combined mass of the 4 protons) is described by Einstein’s famous equation E=mc² and represents the energy released by the reaction in the form of gamma rays. In order to accomplish this, for the individual protons to get close enough to each other to combine thr0ugh the Strong Nuclear force, overcoming the electrostatic barrier that repels them, the plasma (ionized hydrogen consisting of free protons and electrons) temperature is measured in many millions of degrees. This requirement has been the technical barrier to the development of nuclear fusion as a viable energy source. However, this is not a barrier to the use of it in the production of a weapon.
The Use of Nuclear Energy as a Weapon
The use of either of these two nuclear processes as a weapon, either nuclear fission or nuclear fusion, is a malignant perversion of the lowest order; to use the same process by which nature builds the raw materials for new life as a means to destroy that life is as perverse as it is extreme. It is through repeated nuclear burning cycles of heavier and heavier nuclei in high-mass stars that we build the raw materials for life and, in the spectacular death of that high-mass star in a Type-II supernova, those building blocks enrich the interstellar medium, providing the foundation for new worlds, new life and new civilizations. As we stand in awe of this nature, witness to the terrible beauty of a supernova, we observe that life is born of death; that we, in a perverse irony, in our ignorance and quest for self-destruction, invert that process and turn it on ourselves; this is evil in its purest form.
The weapon North Korea claims to have detonated is a Hydrogen bomb or more precisely, a Thermonuclear bomb, a device that is almost three orders of magnitude (1000x) more powerful than an atomic bomb such as was used against Japan at the end of WWII. The conventional atomic bomb is a two stage device where a high power conventional explosive is used as a trigger to initiate a second stage, a nuclear chain reaction and the commencement of the fission process, unleashing the power of a supernova originally used to build the heavy nuclei. The Thermonuclear weapons deployed by the worlds nuclear powers are of the Teller–Ulam design, a three stage device, where the first two stages essentially follow the conventional fission bomb design with the third stage a fusion boosted fission stage where the super-heated plasma created in the second stage provides the temperature, pressure and environment for fusion to begin via various isotopes of heavy hydrogen thus boosting the efficiency of the fission processes already in play from the second stage and included in the third stage. Staged thermonuclear weapons are essentially a chain of fusion-boosted fission weapons, usually with only two stages in the chain. The *Tsar Bomba, a Russian-produced, three stage thermonuclear weapon produced a yield of over 51 MT, the greatest yield of any weapon ever produced or tested — by anyone.
A pure fusion bomb does not exist and, hopefully, never will.
The results of the North Korea test are still inconclusive but four outcomes are possible:
- the reclusive rogue state tested a conventional nuclear weapon, not a thermonuclear weapon as claimed. Seismic readings and other data suggest that this is the case; still state-controlled media (Kim) insist it was a “Hydrogen Bomb”;
- it was a failed test of a three stage weapon with the second stage failing to ignite the third;
- it was a successful test of a small, low-yield three stage weapon buried deeper in the mountain than previous tests. This result isn’t likely but would be consistent with reports that Pyongyang is developing a small-scale thermonuclear weapon capable of being delivered by a missile. The usual parameters are something less than one meter in diameter and less than one ton in weight.
- A double-stage, Tritium-boosted fission weapon; this would be consistent with Pyongyang’s claim that it is developing a thermonuclear weapon. They may have erected facilities at the Yongbyon nuclear complex consistent with tritium production. Tritium is a radioactive isotope of hydrogen with one proton and two neutrons. The most abundant form of hydrogen is Protium with only one proton and no neutrons.
- *Note: generally, discussions of the various stages of a nuclear weapon omit the high-power conventional explosive as a “stage”; this is not the case in my discussion.
A Solution is Essential
Clearly, the regime cannot be allowed to accomplish its goal of becoming a full nuclear state. A western business-as-usual approach to North Korea will result in more of the same. Kim needs to be regarded as a recalcitrant, impetuous, immature, mal-adjusted child in need of attention. Such a child with access to weapons of mass destruction is what the civilized world is faced with. So, regardless of what actually happened on January 5th in the mountains of North Korea, it is clear that the regime is determined to proceed forward with its nuclear ambitions. Possible solutions begin with an understanding of his psyche; what is driving him? Underlying the behavior of a child who is acting out, there is an certain unfulfilled need. With his saber rattling, I submit he is looking for recognition and that there is a certain rationality behind his actions. Falling short of addressing the larger question of Korean unity and the simmering hostilities between the north and the south, limited diplomatic engagement with an eye towards lifting the crippling sanctions should be the order of the day. Short of a direct attack, a military response is problematic for a hundred reasons and is out of the question. The best hope of halting the regime’s march towards full nuclear statehood begins with limited economic and diplomatic engagement.
J. Robert Oppenheimer
In closing, it should be pointed out that, in addition to his key role in the development of nuclear weapons and his subsequent vocal opposition to their continued proliferation and the development of the thermonuclear bomb, he played key roles in other areas of theoretical physics and astrophysics, notably the derivation of what is known as the TOV (Tolman, Oppenheimer, Volkoff) limit, the mass limit above which a stellar remnant will continue to collapse to form a black hole. This limit is between 1.4 and 3 solar masses. Additional areas of study and contribution include modern theories on the formation, properties and behavior of neutron stars and black holes, quantum mechanics, quantum field theory and the interactions of Cosmic rays. As a teacher and promoter of science, he is remembered as a founding father of the American School of Theoretical Physics, an organization that gained worldwide prominence in the 1930s. After World War II, he received the prestigious title of Director of the Institute for Advanced Study in Princeton, NJ.
*This post’s featured image is the test explosion of the Tsar Bomba over Novaya Zemlya Island in the Russian Arctic Sea on 30 October, 1961. With a theoretical yield of 100 MT, this weapon remains today as the most powerful single weapon ever made.