Cherenkov Radiation

1.12.2022 (revised 1.13.2022)

Today, I learned some science behind Godzilla’s atomic ray. It goes by many terms such atomic fire, radiation flame, fiery breath and so on. In Japanese, the noun regularly used 放射火炎 (ほうしゃかえ, hosha kaen) is a noun, meaning “radiation” or “emission​,” translated “radiant flame” by Google. It goes by the term 白熱光 (hakunetsu hikari) translated “incandescent light” (See post “Pages from 1954”). In the book「Hedorah 公害怪獣の映像世界」”Hedorah Pollution Monster Movie World,” Godzilla’s atomic ray states,「ゴジラの最強の武器で、口から放射能を含む高温の熱線のこと。放射能火炎、白熱光と呼ばれることもある。英語では、ATOMIC RAY。放射前、或いは放射中に背びれが青白く発光するが、作品ごとに熱線の形状・色・威力などは微妙に異なる。」”Godzilla’s strongest weapon, a high-temperature heat ray containing radioactivity from the mouth. It is also called radioactive flame or incandescent light. In English, ATOMIC RAY. The dorsal fin emits pale light before or during radiation, but the shape, color, and power of the heat rays differ slightly from work to work.”

Tomoyuki Tanaka’s introduction to Godzilla provides a thoroughly description of Godzilla’s atomic ray and how it works.



Let’s look into the mechanism of the radiation flame!


Godzilla’s secret weapon was born by a hydrogen bomb experiment.


When hitting an object, the high heat is 100,000 degrees or more


The biggest feature of Godzilla is that it emits blue light from its mouth and burns everything.


This ability is not thought to have been from the beginning, so it is considered to be the result of the impact of hydrogen bomb experiment.


Minya also puts out a radiation flame, but this is because when Minya’s egg was in the stomach of his mother monster, the mother monster could have been involved in the hydrogen bomb experiment and this is said to may have been the cause.


This pale ray is a collection of radiation flame energies, and it is thought that if it strikes an object it will reach a temperature of over 100,000 degrees. This ray is called incandescent light or radiation flame.


Dorsal finally glows pale blue.


For the body of Godzilla, it seems that there is a reaction bag which works like a nuclear reactor. Among them, nuclear materials in Godzilla’s body are gradually becoming energy gradually while emitting radiation flames.


This mechanism is somewhat similar to humans converting carbohydrates and fats into energy in the body.


Beside the reaction bag, there is a uranium sack that holds nuclear material.



When Godzilla gets angry and inhales a lot of breath, the lung bulges and pushes the uranium bag. In doing so, a large amount of nuclear material flows into the reaction bag, and energy is generated at once.


Next, when he breathes out, energy is dragged by it, energy flows to the trachea and comes out of his mouth with breath.


At this time, electromagnetism occurs in the reaction bag, so that energy is not exposed to the inside of the trachea and mouth, and furthermore the direction of the energy is for one thing. Radiant energy emitted from the mouth acts with the atmosphere and glows pale blue like an aurora. This is a radiation flame.


When radiant flames are applied, the whole body is covered with a radiation flame, particularly concentrated on the back of the back. Because of that, the dorsal finally glows pale blue.


The figure on the left illustrates how Godzilla radiates flames.

発光現象 Emission phenomenon
気管 Trachea
放射火炎 Radiation flame
ウラン袋 Uranium bag
肺 Lung
磁力線 Line of magnetic force
放射火炎エネルギー Radiation Flame Energy
反応袋 Reaction bag
放射線 Radiation

Today, I learned some science behind the bluish hue of Godzilla atomic ray. The blue is the result of Cherenkov radiation. “Cherenkov radiation is electromagnetic radiation emitted when a charged particle passes through a dielectric medium at a speed greater than the phase velocity of light in that medium. A classic example of Cherenkov radiation is the characteristic blue glow of an underwater nuclear reactor. The phenomenon is named after Soviet physicist Pavel Cherenkov, who shared the 1958 Nobel Prize in Physics for its discovery.” (Source: Wikipedia).

Take a look at how the Cherenkov radiation works in this excellent video with Dr. Don Lincoln. Imagine the charged particles or lines of magnetic force (磁力線) traveling in Godzilla’s body and Uranium bag (ウラン袋) faster than light travels. As Godzilla spews his atomic ray the blue and violet light is emitted from his dorsal fins.

I owe this insight to フジストロン @Pczp1VPUvTPps17 on twitter, where he speculates if the blue light of Godzilla’s flame is indeed Cherenkov light then it must be the result of a reaction with water vapor in the air, because the Cherenkov occurs in water. ゴジゴジ(あけおめ) @Godzilla1914189 replied,「体内の原子炉でスパークさせて放射してああなってるのでチェレンコフの塊なのは間違いないですね~」”There is no doubt that it is a cluster of Cherenkov because it sparks in the nuclear reactor inside the body and radiates it.” And this makes sense based on Godzilla’s anatomy and the definition of the Cherenkov radiation.

The Cherenkov radiation is confirmed later in Tanaka’s introduction on page 175 in the Godzilla Terminology Dictionary (ゴジラ用語辞典):


Pale Blue Light: When he shoots a flame, the back of Godzilla shines pale blue. In the evening, the whole body may be shining pale blue. This seems to be due to X radiation. Also, when underwater, he always emits a strong light. This is thought to be Cherenkov radiation light emitted when radiation passes through water.

Godzilla’s blue atomic ray first appeared in King Kong vs Godzilla (1962), which was the first Godzilla film in color. A UN nuclear submarine was investigating the rise in water temperature in the Arctic Ocean when they came upon a mysterious iceberg glowing pale light blue. Little did they know that Godzilla was buried inside since the ending of Godzilla Raids Again (1955). The doctor was asked to explain the light. He replied, “It looks like the Cherenkov light… Yes, it’s light generated in nuclear reactor. That light looks very much like…”「チェレンコフ光のようです…原子炉に発する光ですよく似ています」.

The power of Godzilla’s atomic ray is rooted in his origin. It was the result of the U.S. H-bomb test test over the Bikini Atoll on March 1, 1954. The flash was seen by the crew of the Japanese fishing boat, the Lucky Dragon No 5, who are represented by and memorialized in the story of Gojira (1954). Like the Japanese fishermen, the legendary dinosaur called “Gojira” by the people of Odo Island, is mutated by the atomic blast resulting in his black rugged scorched skin. Soon after, Godzilla lands in Tokyo, setting it ablaze with his atomic ray conjuring the memories of the atomic bombs dropped on Hiroshima and Nagasaki at the conclusion of Word War II in 1945.