As the Artemis II crew orbits the Moon, millions of miles from Earth, the four-person team is breaking records for human distance from home. But inside the compact Orion Multi-Purpose Crew Vehicle, a 330-cubic-foot capsule roughly the size of two minivans, the most vital piece of technology isn’t a thruster or a navigation sensor—it is the Universal Waste Management System (UWMS).

Designing a toilet for deep space is an exercise in extreme engineering. In the weightless environment of microgravity, where liquids and solids do not “fall,” NASA engineers had to reinvent the most basic human necessity for a mission where failure is not an option.

Background: From Apollo Bags to the Universal Standard

The history of space toilets is notoriously messy. During the Apollo era, astronauts relied on “fecal containment bags”—plastic pouches taped to their buttocks—and urine collection devices that often leaked. The Space Shuttle and International Space Station (ISS) introduced more advanced vacuum-based systems, but these were bulky and difficult to maintain.

The UWMS represents a “universal” leap forward. Designed by Collins Aerospace in collaboration with NASA, it is a modular system intended for use across multiple platforms, from the Orion capsule to future lunar outposts and Mars-bound habitats. The Orion version is specifically optimized for deep-space constraints: it is 65% smaller and 40% lighter than the current ISS toilet to fit the cramped quarters of the crew module.

Technical Design: Suction, Separators, and “The Fan”

At the heart of the $23 million system is high-speed airflow. Since gravity cannot pull waste away from the body, the UWMS uses a powerful internal fan to create a vacuum effect.

The Dual Fan Separator (DFS): A masterpiece of miniaturization, the DFS uses a single motor and shaft to drive two separate functions: entraining waste into the system and separating liquids from air.

The Urine Funnel: For liquid waste, each astronaut has a personal, titanium-fabricated funnel connected to a hose. The airflow pulls the urine into the DFS, where it is centrifuged to separate the liquid from the air stream.

The Commode: For solid waste, the system features a 5-inch seat—significantly smaller than a standard Earth toilet—designed to ensure a tight seal. Solid waste is pulled by airflow into a specialized fecal canister.

Acoustics and Privacy: The system is located in the “Hygiene Bay,” the only room in Orion with a solid door. Because the high-powered fans are incredibly loud—averaging over 72 decibels—astronauts often wear hearing protection while using it.

Operational Working: Where Does it All Go?

The operational lifecycle of waste on Orion differs significantly from the ISS. While the ISS recycles 98% of its water (including urine), the 10-day Artemis II mission lacks the weight allowance for a massive recycling plant.

Urine Venting: Once separated by the DFS, urine is pre-treated with chemicals to prevent mineral buildup and microbial growth. It is then vented directly into the vacuum of space. Outside the spacecraft, the liquid instantly freezes into tiny, sparkling ice crystals—a phenomenon astronauts sometimes jokingly refer to as “the Constellation Urion”.

Solid Waste Storage: Fecal matter is collected in odor-controlled canisters. Once a deposit is made, the crew must manually “compact” the waste using a specialized tool to maximize storage space. These canisters are sealed and returned to Earth for disposal.

Stability in Microgravity: To prevent “floating away” during use, the Hygiene Bay is equipped with handholds and foot tethers. “You need handholds because you’re just floating up all over the place,” explains NASA astronaut Christina Koch. “You need to keep yourself down on the toilet seat”.

Recent Challenges: Troubleshooting the High-Tech Loo

Even the most advanced plumbing can have “bad days.” Early in the Artemis II mission, the crew reported a blinking fault light on the UWMS. After initial troubleshooting, the crew had to temporarily use “collapsible contingency urinal devices”—essentially high-tech pee bags—while mission control analyzed the data.

Engineers eventually identified a “priming issue” where the motor needed time to warm up after sitting dormant. A wastewater vent line also required clearing by orienting the spacecraft toward the Sun to melt potential ice blockages. The crew successfully restored the system to normal operations, a testament to the rigorous “shakedown” nature of the Artemis II test flight.

As NASA looks toward Mars, the UWMS on Orion is more than just a convenience; it is a critical test of the life-support systems required to sustain human life across the solar system.

CHEAT SHEET

Here are the technical specifications and features of the Orion toilet: 

Design & Technology: The UWMS is a suction-based system that uses air flow to move waste away from theastronaut,similar to International Space Station (ISS) technology, but more compact.

Waste Separation: The system separates urine and feces. Urine is collected via a hose, while feces are stored in a fecal canister for disposal.

Waste Handling:

Urine: In the Orion capsule, urine is typically vented out of the spacecraft into space, though the system is designed to allow for future recycling technology.

Feces: Fecal waste is trapped in a bag, sealed, and stored in a hard-sided canister for disposal upon return to Earth.

Physical Features:

Location: The system is installed in the floor of the capsule but is surrounded by a curtain to provide a private “hygiene bay”.

Usability: It is designed to be more accommodating to female astronauts compared to previous generations, with a more ergonomic design for both male and female use.

Dimensions: It is roughly the size of a toilet on a small passenger plane.

Operation: It uses a “no-lift” system with foot-operated, foldable, or adjustable stirrups/handholds to help the user secure themselves in microgravity.

Troubleshooting & Contingencies (Artemis II):

The toilet uses heated plumbing to prevent freezing of vent lines (a lesson learned from Apollo). It features a “Collapsible Contingency Urinal” (CCU) for back-up use.

The system includes a noise-reducing feature (though it still requires ear protection) and is surrounded by insulation, which can appear as “orange foam” inside the mockup.

Performance: The UWMS represents a significant size and weight reduction over previous systems, 3D-printed from titanium for durability.