http://www.youtube.com/watch?v=94-puZit3DA

(YouTube: canadianspaceagency)

ONE OF THE CHALLENGES of modern space travel is the fact that living quarters have to be able to accommodate someone living in space for weeks or months at a time.

Where the first manned space missions lasted only hours, and the Apollo missions only days, trips to the International Space Station now routinely last for six months. (The record for the longest trip to space is held by Valeri Polyakov, who was on board Mir for 437 days between January 1994 and March 1995).

As a result, astronauts must worry not only about getting used to zero-gravity toilets and the like, but also more long-running concerns – like how to shave without running water.

Here’s the current commander of the International Space Station, Canada’s Chris Hadfield, with your guide on how to keep your face trim in Zero G.

Super special bonus content: how do you brush your teeth in space?

(YouTube: canadianspaceagency)

Read: How fast is the Internet in space? 8 things we learned from an astronaut’s son