Ask the Chatbot Games & Quizzes ProCon History & Society Science & Tech Biographies Animals & Nature Geography & Travel Arts & Culture Money Videos
meltdown
Table of Contents
Introduction References & Edit History
Images
damage at Fukushima Daiichi power plant
Related Questions
Read Next
Abandoned school in Pripyat in the explosion at the Chernobyl nuclear plant
Nuclear Exclusion Zones
Abstract vector hi speed internet technology background
History of Technology Timeline
Binary Computer Code, Binary Code, Internet, Technology, Password, Data
How Does Wi-Fi Work?
Wide angle view of Pripyat from Polissya Hotel. Chernobyl nuclear power plant zone of alienation.
30th Anniversary of Chernobyl
Discover
Thanksgiving Celebration Traditional Dinner Setting Food Concept
Why Is Thanksgiving in the U.S. Celebrated on a Thursday?
New York NY/ USA- November 23, 2018 Hordes of shoppers throng the Macy's Herald Square flagship store in New York looking for bargains on the day after Thanksgiving, Black Friday.
Why Is It Called Black Friday?
Leonardo da Vinci (1452-1519), Italian Renaissance painter from Florence. Engraving by Cosomo Colombini (d. 1812) after a Leonardo self portrait. Ca. 1500.
10 Famous Artworks by Leonardo da Vinci
Rural Irish landscape, Sligo, Ireland.
Why Is Ireland Two Countries?
A Factory Interior, watercolor, pen and gray ink, graphite, and white goache on wove paper by unknown artist, c. 1871-91; in the Yale Center for British Art. Industrial Revolution England
Inventors and Inventions of the Industrial Revolution
Los Angeles Police Department wanted flyer on Elizabeth Short, aka the "Black Dahlia," who was brutally murdered in January 1947. The FBI supported the Los Angeles Police Department in the case, including by identifying Short through her fingerprints that
America’s 5 Most Notorious Cold Cases (Including One You May Have Thought Was Already Solved)
Title: Senate Square, St. Petersburg, December 14, 1825: repression of the troop mutiny - watercolor by Carl Ivanovitch Kollman, 1825 depicts Decembrist uprising clashing with cavalry, with spectators watching. (new style December 26, 1825) Europe. Saint
8 of the Largest Empires in History
damage at Fukushima Daiichi power plant
damage at Fukushima Daiichi power plant Two of the damaged containment buildings at the Fukushima Daiichi nuclear power plant, northeastern Fukushima prefecture, Japan, several days after the March 11, 2011, earthquake and tsunami that crippled the installation.

meltdown

nuclear physics
verifiedCite
While every effort has been made to follow citation style rules, there may be some discrepancies. Please refer to the appropriate style manual or other sources if you have any questions.
Select Citation Style
Share
Share to social media
URL
https://www.britannica.com/technology/meltdown
Feedback
Corrections? Updates? Omissions? Let us know if you have suggestions to improve this article (requires login).
Thank you for your feedback

Our editors will review what you’ve submitted and determine whether to revise the article.

External Websites
Written and fact-checked by
The Editors of Encyclopaedia Britannica
Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree. They write new content and verify and edit content received from contributors.
The Editors of Encyclopaedia Britannica
Article History

meltdown, occurrence in which a huge amount of thermal energy and radiation is released as a result of an uncontrolled chain reaction in a nuclear power reactor. The chain reaction that occurs in the reactor’s core must be carefully regulated by control rods, which absorb neutrons, and a moderator, which reduces their energy. If the core becomes too hot, it can melt, releasing large amounts of radiation. See also Three Mile Island accident of 1979, Chernobyl accidentof 1986, and Fukushima accident of 2011.

The Editors of Encyclopaedia BritannicaThis article was most recently revised and updated by William L. Hosch.