What is the difference between a thermonuclear and nuclear bomb

All the developments since the UN tightened sanctions on North Korea. More from News. Russian oil magnate who sued Rothschild sees NY case dismissed. UN rep slams Lebanon central bank chief over economic crisis. Poland-Belarus border: What you need to know about the crisis. Most Read. Should nations go nuclear to save the planet? Atomic bombs rely on fission, or atom-splitting, just as nuclear power plants do. The hydrogen bomb, also called the thermonuclear bomb, uses fusion, or atomic nuclei coming together, to produce explosive energy.

Stars also produce energy through fusion. The amount of energy is huge. More compact: Hydrogen bombs can be made small enough to fit on a head of an intercontinental missile. What's the same: Both the A-bomb and H-bomb use radioactive material like uranium and plutonium for the explosive material.

Here's an example of how much more destructive a hydrogen bomb can be than an atomic one, as calculated by the NUKEMAP tool designed by nuclear-weapons historian Alex Wellerstein. The largest orange circle denotes the thermal radiation radius, the area where the explosion can cause third-degree burns; the green is the radiation radius, where radiation doses are high enough to kill most people over the course of hours or weeks.

If any of North Korea's previous atomic bombs had been dropped on Parliament Hill, the immediate devastation would be confined mostly to Ottawa's downtown core and neighbouring Gatineau. But a blast as powerful as the first-ever hydrogen bomb — codenamed Ivy Mike, detonated by the United States in — would devastate the greater Ottawa area and many neighbouring communities as well.

In an undated file photo, North Korean leader Kim Jong-un looks through a pair of binoculars during an inspection at a forward post off the east coast of the Korean peninsula. North Korea claims Wednesday's test was of a a miniaturized hydrogen nuclear bomb. While seismic data supported the claim of a large explosion, there was no immediate way to verify the type of weapon. The difference between thermonuclear bombs and fission bombs begins at the atomic level.

Fission bombs, like those used to devastate the Japanese cities of Nagasaki and Hiroshima during World War II, work by splitting the nucleus of an atom. When the neutrons, or neutral particles, of the atom's nucleus split, some hit the nuclei of nearby atoms, splitting them, too. The result is a very explosive chain reaction. The bombs dropped on Hiroshima and Nagasaki exploded with the yield of 15 kilotons and 20 kilotons of TNT, respectively, according to the Union of Concerned Scientists.

In contrast, the first test of a thermonuclear weapon, or hydrogen bomb, in the United States in November yielded an explosion on the order of 10, kilotons of TNT.

Thermonuclear bombs start with the same fission reaction that powers atomic bombs — but the majority of the uranium or plutonium in atomic bombs actually goes unused. In a thermonuclear bomb, an additional step means that more of the bomb's explosive power becomes available.