"There's a problem of separation," Roberts said. "Whatever comes out of you doesn't know it's supposed to come away from you." Each fecal collection bag came with a "finger cot" to allow the astronauts to manually move things along. Then they had to knead a germicide into their waste so that gas-expelling bacteria wouldn't flourish inside the sealed bag and cause it to explode. [Space Quiz! The Reality of Life in Orbit]
The entire ordeal often took 45 minutes to an hour to complete in the Apollo spacecraft, Roberts said. To minimize their bowel movements, astronauts had a high-protein, low-residue diet — think steak and eggs and other foods that are don't make a lot of waste after they are absorbed by the body.
Urinating wasn't much easier for the Apollo crews. Their urine collection device was basically a condom-like pouch attached to a hose that vented out into the vacuum of space at the turn of a valve. By the astronauts' own accounts, it was more than a little unsettling to use the device, Roberts said.
Today, going to the bathroom in space is much less tedious, but it still requires careful attention — and even space toilet training. The reusable space planes of NASA's retired shuttle program had toilets using airflow to draw waste away from the body in place of Earth's gravity. The International Space Station has commodes with a similar design.
"For No. 2, it's kind of like a camp potty, where you use that to contain the solid waste and that gets burned up in the atmosphere eventually on a spacecraft," NASA astronaut Nicole Stott told elementary students today (Aug. 29) during a video chat from NASA's International Space Station Mission Control in Houston. "For No. 1, it's basically a hose, we call it a urine hose, that has a vacuum on it."
Astronauts go through "positional training" on Earth to make sure solid waste goes directly into the narrow opening of these space toilets, Roberts explained. The mock toilet has a camera at the bottom. Astronauts don't actually go to the bathroom during training, but by watching a video screen in front of them, they can check that their alignment is spot on.
"If you get stuff around these air vents that are providing the suction in there, things can get really clogged up and you can damage a multimillion-dollar toilet fairly easily," Roberts said.
Breaking a toilet is indeed expensive and inconvenient — not to mention unhealthy. After the sole toilet on the International Space Station had been plagued by a series of problems and breakdowns, NASA bought a second, $19 million Russian commode that was installed in the orbiting outpost's U.S. segment in 2008.