When we sent four humans 406,771 kilometres into space for the first time, we also sent a toilet with them.
After all, if the plan is to go farther and farther, then it’s critical we test one of the non-negotiable parts of being human.
The saga of the Artemis II’s toilet — known officially as the Universal Waste Management System — is a dramedy, unfolding in multiple acts.
Post-launch troubles
The incredible launch of Artemis II on April 1 was nail-biting for people on Earth, but the crew had to immediately get to work.
Mission specialist Christina Koch reported an issue with the toilet about an hour after launch. After a brief communications hiccup, mission control responded.
“We are postulating that the oxone beads came loose and went in and jammed the fan separator,” said Stan Love, NASA astronaut and the crew’s touchpoint at mission control at the time.
“We might be able to get in there and clear it,” Love said.
The fix took a few hours of troubleshooting, with Koch having to essentially reboot the toilet, but to the crew’s relief: it worked.
The Artemis II astronauts connected with Earth via video on Thursday, just after completing the translunar injection burn that is leading them toward the moon, to answer reporters’ questions about their experience so far. Mission specialist Christina Koch declared herself the ‘space plumber’ after fixing a faulty toilet onboard.
“I’m proud to call myself the space plumber,” Koch later told the media. “I like to say that it is probably the most important piece of equipment on board.”
NASA officials later clarified the issue was likely the system automatically shutting off because the pump wasn’t primed with enough water, a hiccup they described as par for the course.
“We’ve got real humans in there,” said Lori Glaze, deputy associate administrator for NASA’s Exploration Systems Development Mission Directorate, at an April 2 news conference.
“They’re trying to live and learn,” Glaze said.
‘A complex engineering issue’
The UWMS, which is located inside a small closet on the floor of the Orion capsule, differs in a few ways from a regular toilet owing to the lack of gravity. For instance, fecal matter is sucked down into a bag that’s sealed and then stored under the floor of the toilet.
Meanwhile, for urine, each astronaut has their own hose that uses some airflow to pull the liquid into storage. The urine is vented several times a day into space, in an impressive frozen stream. Mission control referred to it as a “blizzard” during one particular venting.
But only a couple days in for Artemis II, the lines to vent the urine were getting clogged and frozen. The solution ended up being a rotation of the Orion capsule so that sunlight could hit the vents — melting the frozen wastewater.
“It’s kind of a complex engineering issue when you expose a liquid to a vacuum. It’s a pretty chaotic environment,” said Rick Henfling, Artemis II’s entry flight director, during a media briefing.
The hygiene bay mystery
Meanwhile, inside the capsule, the crew noticed a strange smell emanating from their “bathroom.”
“For me, it was some sort of burning odour,” reported mission specialist and Canadian Space Agency astronaut Jeremy Hansen during a chat with mission control.
“It was definitely in the hygiene bay. And when I opened up the hygiene bay, the rest of the crew could smell it pretty much immediately,” he said.
When NASA looked into it, they ruled out the heaters near the hygiene bay and the use of the toilet itself. They determined it wasn’t dangerous and, eventually, at the April 8 news briefing, Orion deputy program manager Debbie Korth said that no further reports of the smell had come up.
Urinating still a tricky business
From that point, things seemed to be working well until the venting problem reared its head again.
“We just want to let you know that right now, [the] toilet is no-go for use,” said Jenni Gibbons, delivering the bad news to the crew from Houston on Day 5.
The backup plan for the crew is Collapsible Contingency Urinals, which are essentially long tubes that astronauts use to store urine that can also be vented, provided that system is working. While this may seem uncomfortable, note that Apollo astronauts had to use fecal bags that they inserted a germicide into.
Mission control’s theory about what went wrong this time were processes to prevent bacterial structures from forming in the lines.
“There may be something going with a chemical reaction, where there’s some debris that’s generated as part of that reaction and it’s getting clogged in a filter,” Henfling said at an April 7 news conference in Houston.
Though a disappointing malfunction, experts say that’s what to expect from a device like this on its maiden voyage.
“There’s always going to be some shakeout with it, right? There’s going to be things that don’t work,” said John Moores, an associate professor of Earth and space science and engineering at York University and co-host of the Popcorn Science podcast. He says this interplay of systems involving fluids, mechanical and electrical components is one of the more complicated ones on the spacecraft.
The hope — fitting the entire Artemis II mission’s purpose — is that future crews will have the bathroom kinks worked out. When the capsule splashes down in the Pacific Ocean on Friday evening, teams at NASA expect to haul the toilet in for examination to see what went wrong.
“As we go farther and farther out into space, these missions are going to get longer and longer,” Moores said.
“You don’t want go to Mars, which is a journey of months, with a toilet that’s not working for you.”
