Astronaut Demonstrates How to Brush Your Teeth at Zero Gravity

Melissa Knowles

Astronauts are an elite group. But besides being experts at space travel and having superior knowledge of our solar system and the earth itself, astronauts have to become experts at some pretty mundane activities -- doing it all at what is called zero gravity.

In a video uploaded to YouTube titled "Chris Hadfield Brushes His Teeth in Space," by the Canadian Space Agency, Canadian astronaut Chris Hadfield demonstrates a step-by-step guide to brushing your teeth in space. It's way more complex than you might imagine, but it's also pretty cool.

First, Hadfield, who is the commander of Expedition 35, starts with a standard toothbrush and a tube of toothpaste provided by NASA. It does not have a removable cap, leaving one less thing to lose. Hadfield explains that you can't have a running tap or sink of water, because water would go everywhere. So instead, astronauts use a bag that is filled with water and attach a tube or straw-like cylinder to it. Hadfield then carefully squeezes a ball of water out -- just enough to dampen the bristles. Next, he sucks the water off of the bristles. Then he applies toothpaste to the bristles and brushes as he normally would.

He says, "You should brush your teeth for about as long as you can sing 'Happy Birthday.' That should be long enough." Now, Hadfield has a mouth full of toothpaste, and there's nowhere to spit it out. So he simply swallows it. He then says, "It's edible. Won't kill ya."

Viewers are fascinated by the video, with more than 90,000 hits in just a matter of days. One person wrote, "I love how he just leaves the stuff floating each time." That would be pretty convenient. You'd never have to put things away again -- just catch them as they floated by.

Commander Hadfield is a pretty popular guy on Twitter, with more than 600,000 followers. If you're interested in keeping up with his expedition, follow him. He gives regular daily updates about what's going on.

[Related: Astronaut Catches Alien on Space Station in April Fool's Prank]

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