Trivia

Hard

The Interior Of Nuclear Reactor Cores Glow What Color?

Blue
Yellow
Red
Green
Cherenkov radiation glowing in the core of the Advanced Test Reactor.
Argonne National Laboratory/Flickr

Answer: Blue

Pop culture depictions of glowing green radioactive materials like the “ooze” in Teenage Mutant Ninja Turtles or the green glow of radiation at Homer’s nuclear reactor job in The Simpsons have done a remarkable job of cementing the idea in peoples’ heads that radiation is green, green, and more green.

So you might be very surprised to find out that the interior of a nuclear reactor doesn’t glow green at all, but an incredibly serene blue color that belies the danger found therein. The blue glow found in water-submerged nuclear reactor cores is called “Cherenkov radiation”, named after Soviet researcher Pavel Cherenkov, and is a form of 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. In layman’s terms, the glow results from electrons freed during the nuclear reaction zipping along at very high speeds through the water.

Why blue instead of another color on the visible spectrum? Cherenkov radiation is very high frequency and the majority of it isn’t even visible to the human eye (but is in the ultraviolet range just outside the edge of the visible spectrum). The blue we see is the very lowest end of the frequency emitted by the reaction and, just over the frequency line, so to speak, from ultraviolet, and we see it as very bright blue.

Trivia

Hard

Which Planet Was The First To Be Mathematically Predicted Before Direct Observation?

Trivia

Hard

Gummy Bears Were Invented In?

Trivia

Hard

Some Surgeons Have Eschewed Steel Blades In Favor Of Sharper Scalpel Blades Made Of?

Trivia

Hard

What Star Trek Continuity Error Was Left Unexplained For 26 Years?

Trivia

Hard

Which City Was The First To Have A Municipal Wi-Fi System?

Trivia

Easy

Robert Lucas, the 1995 Nobel Prize Winner In Economics, Lost Half His Award Money To?

Trivia

Easy

Which Of These Aquatic Animals Doesn’t Actually Swim?

Trivia

Hard

The First European Country To Adopt The Table Fork Was?

Trivia

Easy

What Did The First Webcam Monitor?

Trivia

Easy

What Common Culinary Vegetable Was Considered Poisonous In 18th Century Europe?