Artemis II Astronauts Report Burning Smell From $23M Toilet Malfunction

Crew addresses issue with advanced waste management system during moon mission

Apr. 4, 2026 at 5:40pm

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Astronauts aboard the Artemis II mission to the moon reported a mysterious burning smell coming from the $23 million advanced toilet system, which had previously experienced a malfunction shortly after launch. The crew described the scent as similar to an old electric heater, but the source was never definitively identified. NASA flight controllers said there were no major concerns, and the astronauts were cleared to continue using the commode.

Why it matters

The Artemis II mission is a critical step in NASA's plans to return humans to the lunar surface, so any issues with the spacecraft's systems are closely monitored. The advanced toilet is a key piece of life support equipment, and its malfunction highlights the challenges of maintaining complex systems during long-duration spaceflight.

The details

After the initial toilet malfunction following the Artemis II launch on April 1, astronaut Chrisna Koch was able to quickly address the issue with the urine hose in the Upper Waste Management System. However, the crew later reported a mysterious burning smell coming from the toilet area, which flight controllers suspected may have been related to the orange insulation on the hygiene bay door. The source of the odor was never conclusively identified, but NASA said there were no major concerns and the astronauts were cleared to continue using the toilet.

  • On April 1, the Artemis II mission launched from Kennedy Space Center.
  • On the following day, April 2, astronaut Chrisna Koch fixed the initial toilet malfunction.
  • On Saturday, April 6, the crew reported the burning smell coming from the toilet area.

The players

Chrisna Koch

An astronaut on the Artemis II mission who addressed the initial toilet malfunction shortly after launch.

NASA

The U.S. space agency overseeing the Artemis II mission to the moon, including monitoring the spacecraft's systems and providing guidance to the crew.

Artemis II

NASA's second crewed mission to the moon as part of the Artemis program, which aims to establish a sustainable human presence on the lunar surface.

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What they’re saying

“Regarding the smell, I just wanted to make sure you all were tracking the EGS notes of the kind of burning heater smell that was coming from toilet several times.”

— Chrisna Koch, Astronaut

“It was never identified as the source, what it exactly was, but it was identified as an unknown smell.”

— Chrisna Koch, Astronaut

What’s next

NASA flight controllers will continue to monitor the Artemis II spacecraft's systems, including the advanced toilet, as the mission progresses. The crew has been cleared to continue using the commode, but any further issues will be closely examined.

The takeaway

The Artemis II mission has faced early technical challenges, including a malfunction with the spacecraft's $23 million toilet system. While the crew was able to address the initial issue, the subsequent mysterious burning smell highlights the complexities of maintaining critical life support equipment during long-duration spaceflight. NASA will need to ensure the reliability of such systems as it works toward its goal of sustainable human exploration of the moon.