There's no going back on your word, even in space.
With the United States and Germany facing each other in the 2014 FIFA World Cup last week, American astronauts Reid Wiseman and Steve Swanson and German astronaut Alexander Gerst made a bet on the game—while in space.
The terms of the bet were pretty simple. If Germany won, Wiseman and Swanson had to get their heads shaved. If the United States won, the American astronauts would be able to paint the United States flag on Gerst's head.
Although the United States did end up advancing out of group stage last Thursday, Germany managed to pull out a 1-0 victory over Team USA to win Group G. That meant that the American astronauts had to say goodbye to their hair!