Astronaut Fred Gregory is the front-runner for Worst Thanksgiving Ever. His tale of a plumbing failure while on the zero-g toilet resulting in a very personal depressurization under a gushing torrent of freezing oxygen still makes us cringe over a decade later.


This story takes during STS-33, a classified flight space shuttle Discovery in November 1989. This story is retold by Wanye Hale who was serving as Orbit 1 team Flight Director with a shift starting at noon on Thanksgiving day, and he swears it was “mostly true.”

November 22, 1989: Launch of space shuttle Discovery on mission STS-33. Image credit: NASA


Before we get started, it’s important to understand the challenges of going to the bathroom in space. While disposing of liquid waste in space is relatively easy, solid waste is trickier since as Hale delicately explains, it “tends not to be removed from the body.” In early space shuttle designs, this problem was solved with a complicated “slinger/shredder” mechanism, but astronauts objected to having a rapidly-whirling mechanism positioned so closely to their bits so the version eventually put into use relied on a small fan and airflow instead.

To use a toilet in space, astronauts position themselves over a very small hole held in place with a lapbelt and feet stirrups. They gear-shift to close the vacuum valve, shifting again to open the slider valve, and the final shift starts the small fan to circulate air. Business complete, the astronauts reverse-shift to turn the fan off, close the slider valve, and reopen the vacuum vent to deal with any quiescent odours.

STS-33: crap toilet, but excellent views. Image credit: NASA


Early on Thanksgiving morning, astronaut Fred Gregory awoke to use the facilities. Carefully positioned, he started the gear shifting. But the mechanism broke after he finished his business: the vacuum vent opened, but the slider valve failed to close. Depressurization! If that’s not bad enough to have the suction of pure space applied to the most delicate of regions, a sadistic quirk of spacecraft design means that all fresh air for the shuttle enters through the roof of the bathroom. Extremely cold, barely-heated-above-liquid fresh air rushed down on Gregory as the depressurization klaxon rang out, waking all his companions.

Astronaut Story Musgrave was the one to rescue Gregory, jamming the slider valve closed while John Blaha started running down the emergency procedures for a cabin leak. Everyone now thoroughly awakened (and Gregory with a frosty bottom), the bathroom was shut for maintenance while Mission Control tried to work the problem from the ground.



If they couldn’t find a way to fix the toilet, the crew would need to break out the Apollo bags for the rest of the trip. Hale discretely explains why that’s such an unpleasant idea:

If you don’t know what an Apollo bag is, well . . . let’s just say that you really didn’t really want to know. It’s a big plastic bag with sticky substance on the lip which you apply to your . . . anatomy . . . to take care of your . . . business. Not glamorous.

Mission Control called in the engineering team from their Thanksgiving holiday, tearing apart the ground copy of the Waste Collection System to pounder a fix. The solution came from the In Flight Maintenance team who figured out that if the astronauts ripped off the front cover, they could use a pair of vise-grip pliers on the appropriate lever to resume using the toilet for the rest of the mission without risking depressurizing the cabin again.

Toilet repaired and chaos subdued, the crew sat down for their only joint meal of the mission: turkey, potatoes, and broccoli.


The toilet onboard the International Space Station is based on the MIR design instead, preventing future astronauts from getting stranded in the same highly-undignified manner.

November 28, 1989: Landing of space shuttle Discovery marking the end of mission STS-33. Image credit: NASA


Top image: The crew of STS-33 including the unlucky Fred Gregory. Credit: NASA

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