Contrails Are A Hot Topic, But What Is To Be Done?

Most of us first spot them as children—the white lines in the blue sky that are the telltale sign of a flight overhead. Contrails are an instant visual reminder of air travel, and a source of much controversy in recent decades. Put aside the overblown conspiracies, though, and there are some genuine scientific concerns to explore.

See, those white streaks planes leave in the sky aren’t just eye-catching. It seems they may also be having a notable impact on our climate. Recent research shows their warming effect is comparable to the impact of aviation’s CO2 emissions. The question is then simple—how do we stop these icy lines from heating our precious Earth?

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See The Radioactive World With This Peltier Cloud Chamber

Remember when a homemade cloud chamber was a science fair staple? We haven’t participated for decades, but it seemed like every year someone would put a hunk of dry ice in a fish tank, add a little alcohol, and with the lighting just right – which it never was in the gymnasium – you might be lucky enough to see a few contrails in the supersaturated vapor as the occasional stray bit of background radiation whizzed through the apparatus.

Done right, the classic cloud chamber is a great demonstration, but stocking enough dry ice to keep the fun going is a bit of a drag. That’s where this Peltier-cooled cloud chamber comes into its own. [mosivers] spares no expense at making a more permanent, turn-key cloud chamber, which is perched atop a laser-cut acrylic case. Inside that is an ATX power supply which runs a Peltier thermoelectric cooling module. Coupled with a CPU cooler, the TEC is able to drive the chamber temperature down to a chilly -42°C, with a strip of white LEDs providing the required side-lighting. The video below gives a tour of the machine and shows a few traces from a chunk of pitchblende; it’s all pretty tame until [mosivers] turns on his special modification – a high-voltage grid powered by a scrapped electronic fly swatter. That really kicks up the action, and even lets thoriated TIG welding electrodes be used as a decent source of alpha particles.

It’s been a while since we’ve seen a Peltier cloud chamber build around here, which is too bad because they’re great tools for engaging young minds as well as for discovery. And if you use one right, it just might make you as famous as your mother.

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