Space Toilet May Get a Road Test

This story was updated at 5:08 p.m. EDT.

The newest bathroom aboard the International Space Station will have to wait for a vital road test, even though the space shuttle Discovery?s crew has more than tripled the orbiting lab?s population.

Discovery?s seven astronauts arrived at the space station late Tuesday to receive a warm welcome from the outpost?s three-person crew. But delays launching the shuttle forced NASA to trim some objectives from Discovery?s flight, including a spacewalk, flight day and, sadly, the planned test of the station?s new orbital loo.

NASA space operations chief Bill Gerstenmaier told SPACE.com just after Discovery?s Sunday launch that station mission planners were hopeful they could still fit the space toilet test in Discovery?s mission. But the test must now wait until after repairs to the station?s urine recycling system and a water dispenser, NASA officials told SPACE.com Wednesday.

Space station commander Michael Fincke sent Discovery?s crew a video tour of the station?s new bathroom when plans were in place to have the astronauts aboard help test the space toilet?s capacity to make sure it was ready to support six long-term residents. While Fincke?s crew currently numbers three astronauts, the station is slated to double its occupancy up to six people in late May.

?You guys are going to get to try it out,? station commander Michael Fincke told Discovery?s crew in a recent video tour of the new bathroom.

A NASA spokesperson said the toilet is available for use by astronauts aboard the station, but won?t be tested for its capacity during the eight days Discovery is docked at the orbital lab. The shuttle launched to the space station late Sunday to deliver the last piece of the outpost?s backbone-like main truss, a final pair of U.S. solar arrays and new station crewmember Koichi Wakata of Japan.

Discovery also delivered a vital spare part for the outpost?s urine recycling system and equipment to help eliminate bacteria in a new water dispenser. The repairs are expected to fix the station?s water recycling system and help the outpost support larger crews.

NASA officials said that installing the spare part to revive the urine recycler took precedence over the space toilet test during Discovery?s flight.

A new orbital loo

Delivered last November, the space station?s new bathroom fits in a wall space about the size of a large refrigerator. It is based on a Russian design, cost about $90 million and has a complicated-looking instruction panel complete with buttons and lights.

An emblem on its back wall shows a spacewalking astronaut with a roll of toilet paper in hand and the slogan ?Orbital Outhouse Team.?

?Some fine folks in Russian and the United States built it,? Fincke said.

Thise station?s new bathroom is installed in the outpost?s American segment. It was a welcome addition to the station, which for nearly a decade housed two and three-person crews with only one bathroom in its Russian-built segment. (Of the 10 astronauts now on station, those who don't use the new bathroom can use the old one or Discovery?s own space commode.)

The new bathroom was installed alongside extra life support, kitchen and exercise gear, also aimed at dealing with larger permanent crews.

So exactly how do you go to the bathroom in space? Very carefully, and by the book, Fincke said.

?We have two kinds of toilet paper, Russian-style and American-style,? Fincke said in his video tour. Wet wipes are also available and, like bathrooms on Earth, there?s a handy trash bag and a stash of extra supplies.

Unlike on Earth, there?s no gravity in space to help flush waste down a toilet. Instead, astronauts rely on fans and airflow to carry waste away for disposal.

One vital caution from Fincke: if the big red light pops up, call a station crewmember. It means the urine tanks are full.

?We monitor those pretty carefully, so hopefully it should never be a surprise to us,? Fincke said in his video. ?But with a lot of people, you never know.?

SPACE.com is providing continuous coverage of STS-119 with reporter Clara Moskowitz at Cape Canaveral and senior editor Tariq Malik in New York. Click here for mission updates and SPACE.com's live NASA TV video feed.

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