Computers & Mobile Science

Video courtesy YouTube user wlsoundman.

Like me, you’ve probably seen lots of photographs of Cherenkov radiation (Wikipedia), which is the striking blue glow that surrounds nuclear fuel rods submerged in water. It’s caused by charged particles travelling through the water at a speed faster than the speed of light in water (which is about 75% percent of the speed of light in a vacuum).

But this video of Penn State’s Breazeale nuclear reactor “pulsing” is the first time I’ve ever seen any moving pictures of the phenomenon, which are somehow way more impressive. And since this is a phenomenon few of us will ever have an opportunity to witness first-hand, the 15 seconds it takes to watch the video definitely count as time well spent in my book. Note how the blue glow persists for some time after the reactor itself has been shut off.

[Thanks, William Beaty!]

6 thoughts on “Nuclear reactor test footage

  1. Showing me a reactor pulse at their TRIGA reactor is how UT got me into grad school. The sound you hear is a control rod being ejected from the core pneumatically. This causes a very rapid orders-of-magnitude increase in power. Fuel temperature feedbacks kill the reactor before the control rod even falls back down which gives you that magnificent blue flash.

  2. That is awesome.

    Too bad Cal decommissioned their TRIGA reactor 20 years ago. Then again, the idea of a research reactor in Berkeley does seem like it would create some controversy today…

  3. …makes it prettier for me. I feel the same way about metallic mercury: It’s cool to begin with, but the fact that it’s bad for me somehow makes it even more intriguing.

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I am descended from 5,000 generations of tool-using primates. Also, I went to college and stuff. I am a long-time contributor to MAKE magazine and My work has also appeared in ReadyMade, c't – Magazin für Computertechnik, and The Wall Street Journal.

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