Astronauts face bit of a stink after international space station's ONLY loo breaks down

NASA may have to arrange a plumbing service call when space shuttle Discovery visits next week.

Until then, the three-man crew will have to manage with a makeshift system.

An astronaut works on the outside of the International Space Station, confident in the knowledge that although it has only one toilet, nothing could possibly go wrong...

While one of the crew was using the Russian-made toilet last week, the toilet motor fan stopped working, according to NASA.

Since then, the liquid waste gathering part of the toilet has been working intermittently.

Fortunately, the solid waste collecting part is functioning normally.

Russian officials do not know the cause of the problem and the crew has been unable to fix it.

The crew has used the toilet on the Soyuz return capsule, but it has a limited capacity.

They are now are using a back-up bag-like collection system that can be connected to the broken toilet, according to NASA.

"Like any home anywhere the importance of having a working bathroom is obvious," a NASA spokesman said.

The 7-year-old toilet has broken once before but not for as long a time, said Johnson Space Centre spokeswoman Nicole Cloutier in Houston.

Discovery is already set for launch on Saturday with a planned docking with the space station on Monday.

Cloutier said NASA officials are considering having some parts flown to Cape Canaveral and placed in the shuttle during its countdown, an unusual and delicate situation.

Because the shuttle's payload weight is limited and balance carefully calculated, it will be tricky to try to figure out where the parts can go, said Kennedy Space Centre spokesman Bill Johnson.

Discovery's main payload, a 32,000lb (14,515kg) Japanese laboratory addition, is so big that the shuttle's boom sensor system had to be removed to make room for the lab.