According to Agence Free Press:
Toilet troubles on the International Space Station (ISS) could force Russian cosmonauts to return to Earth early, a Russian official told Interfax news agency Tuesday. “It’s true, we have a problem with the flushing system. This is a serious matter,” warned Vladimir Solovyov, chief ground control official for the Russian section of the ISS. “In such circumstances there’s even the possibility of an emergency departure from the station.” The main ISS toilet broke down last week, forcing the crew, two Russians and one American, to use back-up facilities. The U.S. shuttle Discovery delivered spare parts Monday, as well as an extra seven astronauts.
A few thoughts: If you’re having bathroom problems, you’d think the last thing you need is “an extra seven astronauts.” Also, how do you use a plunger in space? And finally, I think we all know the source of the toilet breakdown: How do you say “courtesy flush” in Russian?
