The Artemis II astronauts were back on Earth for less than a day before worms took their place in space. The space worms launched from Cape Canaveral, Florida, on April 11, aboard NASA’s Commercial Resupply Services 24 mission (CRS-24) and are on a journey to the International Space Station (ISS). Although uncrewed, the roughly 11,000 pounds of cargo aboard the Northrop Grumman Cygnus XL spacecraft contained at least few living organisms, including a vat filled with tiny Caenorhabditis elegans nematodes.
Scientists at the University of Exeter in England are relying on the C. elegans worms to investigate a major hurdle facing long-duration spacefaring—safeguarding the health of human explorers. While April 12 marked the 65th anniversary of the first person to reach space, the record for longest time spent in space still remains the 371-day tenure achieved by NASA astronaut and former ISS crewmember Frank Rubio in 2023. Barely a year in microgravity has serious effects on his body that can require extensive physical reconditioning. If humans are expected to establish a permanent lunar base—let alone make the yearslong trip to Mars and back—then scientists and medical experts need to develop a plan to address problems like bone and muscle loss, vision issues, and radiation exposure.
“NASA’s Artemis program marks a new era of human exploration, with astronauts set to live and work on the moon for extended periods for the first time,” Tim Etheridge, a physiologist at University of Exeter,said in a statement. “To do that safely, we need to understand how the body responds to the extreme conditions of deep space.”
Nematodes may not resemble humans at first glance, but both species still rely on many of the same basic biological processes to survive. Once the “Petri Pod” filled with 1-millimeter-long worms arrives at the ISS, crewmembers will transport the multichamber housing container into an onboard laboratory. After some time inside the capsule, astronauts will then use an exterior robotic arm to mount the nematode home onto the outside of the ISS. From there, the nematodes will live for up to 15 weeks inside containers carefully designed to maintain temperature, pressure, and oxygen while still exposed to zero-gravity and the harsh radiation of space.
Back on Earth, researchers will continually monitor the worms’ health using white and fluorescent optics as well as time-lapse video and photography. The team will pay particularly close attention to radiation dosage while also collecting a wealth of additional information on how the nematodes fare in space. Once completed, the experiment’s results will help the team plan future experiments and assess potential solutions to the challenges of life in microgravity.
“It might sound surprising, but these tiny worms could play a big role in the future of human spaceflight,” added U.K. Space Minister Liz Lloyd.
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