One of our favorite things about Japan is the convenience of just about everything, especially the vending machines. Wherever you are, there’s at least one machine just waiting to quench your thirst–and all of them have any tired writer’s favorite drink: Coffee!

Even more conveniently, though, most machines offer a choice of hot or cold cans–but, of course, the cans will cool down if you don’t drink them right away. In which case you might be tempted to try heating your can up on the stove, like this Japanese Twitter user. That would be a bad idea.

▼”Uh, I meant to do that?”


The photo above was tweeted by @GlamTrick along with the candid message: “When heating can coffee in a pot, do not turn the heat on and walk away. When you return, it may be impaled in the ceiling.

Now anyone with a rudimentary understanding of physics will know that heating things increases the internal pressure as the atoms start moving faster. So, it should hardly be a surprise that coffee cans will explode and launch themselves far into the sky–or ceiling–when heated. But that doesn’t make the results any less spectacular! You can even try it at home by placing an unopened can of beans directly onto an oven range, cranking the heat up, and taking cover behind a counter. (Note: RocketNews24 is not responsible for cleaning your kitchen.)

If you’d like to heat a can, filled with coffee, beans, corn or anything else, and will be obligated to clean the walls in case of an explosion, Suntory has a handy guide for you. First: Don’t do it. Seriously, just open the can and dump the contents into an appropriate container or pan for heating! But if you’re dead set on leaving your coffee in the can, you do have one option, according to the beverage company: Boiling it. Kind of. They recommend boiling a pot of water, turning the heat off, and then putting the can in the water once it’s cooled to between 50 and 60 degrees Celsius (or between 122 and 140 degrees Fahrenheit).

Probably not as much fun to watch…but much cleaner we suppose.


For some reason, quite a few Japanese commenters seemed a bit miffed by the tweet, writing: “What the…?” and “Hunh?” Others were apparently reminded of the greatest show on TV, MythBusters: “It’s like some mysterious legend on the Discovery Channel.” Others were a bit more critical, writing: “Who heats canned coffee in a pot?!” and “Open the tab!”

Obviously, opening the tab would prevent pressure build up and subsequent Micheal Bay-esque food preparation, but it might also cause hot coffee to bubble out. So refer back to Suntory’s tips if you can.

And since we’re talking about exploding cans, here are two Japanese science videos with exploding cans, because…science? And because we love our readers.

First, blowing up a can with gas!

This experiment is performed by basically filling a can with eight times the air pressure of one standard atmosphere.

That was cool, but there was a distinct lack of fire. Fortunately, we also found this…

Blowing up a can with alcohol!

In this video a Japanese YouTube science “teacher” like Bill Nye shows how to…well, basically make a bomb. Cut the top off a can, drill a hole in the side, and pour in a dash of rubbing alcohol. Next, pop a paper cup over the top and, with your finger over the drilled hole and the cup tightly in place, slosh the alcohol around until it gets aerosolized. Then, just use a long lighter to hold a flame next to the drilled hole and…fwoosh!

Oh, and, uh, don’t try this at home kids! Or if you do, tell your parents the devil made you do it and leave our names out of the story!

Sources: Hamusoku, Twitter, Suntory
Images: Twitter, Know Your Meme