Cosmic Ray Detector

This project can help you detect unseen parts of the natural world and rethink nothingness.

Is emptiness really empty? The Zen Buddhism origins of wabi-sabi would lead us to say yes and no, that it both exists and doesn’t. That might seem like a paradox, however it’s not intended as a contradiction. For example, when something is empty, it is full of potential. Even physicists once considered outer space to be filled with an unknown substance they called “ether,” then discovered it was a vacuum largely void of matter (empty), now are beginning to consider it full again, this time with the phenomenon of spacetime that can vibrate, warp and more.

A cosmic ray detector won’t show you spacetime, but it will reveal an unseen world of high-energy sub-atomic particles that race through the so-called void of space and right through our bodies as well. Thousands of these particles pass through our planet, and through us, every second. This natural radiation is harmless and invisible, yet the tracks that the particles leave behind can be seen using a a detector.

Effects

The user begins by patiently watching the cloud chamber device with a flashlight. Cosmic rays cannot normally be seen, heard, smelled or tasted. However with a monitoring setup these hidden visitors from the void will reveal themselves, helping us question our concept of emptiness. We also get a connection to nature on its own terms, a weird, messy space that’s always in flux. It works by using dry ice and alcohol to create a vapor mist. When high-energy particles pass through the cloud the ionize it, leaving traces trillions of times larger than the particle, so big we can see it with the naked eye.

Animated GIF of particles in a cloud chamber.

α particles (helium nuclei) leave short and wide traces, β particles (electrons) give rise to thin, sometimes straight lines. Clear, long and straight traces are produced by cosmic mµons.

Elements

It is almost certain that cosmic ray detectors were not created with wabi-sabi in mind. Yet these detectors share many characteristics that evoke the wabi-sabi ethos, some in a very deep way. The cloud chamber is quite simple, and uses no special or particularly technical equipment. This minimalism is core to wabi-sabi, which eschews the unneeded and ornamental. The device provides a suggestion as to what is unseen, but it’s really only a hint of the myriad invisible phenomena that surround us. Much is left to the virtual shadows, something Tanizaki would have approved of. Particles zooming through us from outer space sound kind of frightening, but they’re as natural as natural can be. Each particle’s traces appear seemingly from nowhere and are just as soon gone, exemplifying the transience fundamental to our universe. Capturing these traces in a cloud chamber is no different from observing falling snow in moonlight. It’s direct contact with the untamed, in a calm process that requires stillness, patience and full attention to the present.

Chamber diagram from OpenPhysicsLab.

Opportunities

I’ve argued that these cloud chambers evoke wabi-sabi just the way they are. Of course, using materials more intimately sourced from nature, adding asymmetry and lovely imperfections could only add to that experience. However wabi-sabi is not only about visual design, it’s also about context and most importantly, the impact of the piece. Consider putting the chamber in an outdoor location, perhaps a dark garden where it could be used at night to highlight the untamed nature of these high energy particles. Engaging more of the senses can also heighten a wabi-sabi experience. Think about listening opportunities. While each particle’s path is displayed silently there is no reason why it only needs to be materialized visually. Using electronics to detect the path (video analysis might work), what noise could it make? A zing? Wooosh? A flute or shamisen? Remember to keep things simple in the end so they aren’t distracting, but rather enhance the experience of materializing the unseen.

Building your own

Cloud chamber instructions are not hard to find. Here are a few options to consider:

Sarah Charley, the US Communications Officer of CERN (European Organization for Nuclear Research) leads a lovely video tutorial, a full instruction manual and even a video of the particles leaving traces. PhysicsOpenLab also hosts a nice set of instructions.

The American Museum of Natural History in New York also offers a great build guide using an aquarium as the cloud chamber.

Kranthi Gunthoti and his daughter Sarah created a very complete tutorial on creating cloud chambers in a simple plastic cup, including a video of the process.

Finally, let’s not forget our friends at Make Magazine, who also host online directions on their site for creating cloud chambers with a basketball display case.

All of these projects require dry ice, which must be handled carefully to avoid frostbite burns meaning children should be supervised during the build. Dry ice is easy to obtain, try the Dry Ice Directory to find local sources. Parents, anything left over can be used to make dry ice Martinis!

Cloud chamber cosmic ray detectors are a great way to celebrate seeing the unseen, and getting a little closer to understanding nature and the nature of emptiness.