In celebration of April 20th, I thought I’d show you a method for making fire that’s so neat it will work — without fuel or chemicals — both on Earth (left) and in space (right).
We’re going to do it without a match, without a lighter, and without friction. That’s right, the next time someone needs a light, I’ll show you a way to make one that even beats rubbing two sticks together!
(Note: I did this myself last month — accidentally — with olive oil in a wok that was too hot. Bad idea.) If you want to set anything aflame, you need to have the temperature rise above the Flash point of the material. For a match, striking the match head against an abrasive surface releases enough chemical energy to allow the underlying wood to ignite. For rubbing two sticks together, you have to put enough mechanical (i.e., frictional heat) energy into the system to get up to that temperature. And for a lighter, the metal sparks from rubbing the steel against flint are at a high enough temperature that they can ignite the butane gas:
Then, compress the piston as quickly as you can. When you compress gas in an airtight container, there are two ways it can happen: isothermally or adiabatically. These fancy words basically mean that if you compress it slowly, the temperature will stay constant, but if you compress it quickly, the temperature will rise.
And if you compress it quickly enough, the temperature can rise by hundreds of degrees Celsius, enough to ignite many flammable materials! And that’s how, just by using your hands, you can start a fire in seconds!
So enjoy today — and every day — and choose your favorite way to make fire!