Microbiology,  biotechnology, and physics were the dominant research themes aboard the International Space Station on Tuesday as the Expedition 74 crew explored how microgravity affects bacteria, cartilage growth, and metallic structure. Scientific hardware maintenance rounded out the schedule for the orbital residents to ensure continuous experimental operations.

NASA flight engineer Jack Hathaway reviewed procedures ahead of an investigation to explore how bacteria adapt to the space environment. Hathaway familiarized himself with the tools and steps he will use to study how two sets of bacterial samples respond to weightlessness. One set will be treated with an antibiotic and the second set will be left alone. After the samples are incubated for five days their DNA will be sequenced for more insight into microbial adaptation to microgravity. Results may lead to advanced efforts to reduce the risk of bacterial infection and help protect an astronaut’s immune system during a spaceflight.

NASA flight engineer Jessica Meir nourished cartilage tissue samples inside the Kibo laboratory module’s Life Science Glovebox that are growing to gain a better understanding of the function of cartilage cells and tissue in microgravity. The tissue samples are being engineered aboard the orbiting lab to understand how cartilage develops and repairs itself possibly improving astronaut fitness regimens and promoting the development of advanced implants on Earth.

NASA flight engineer Chris Williams inserted StarSteel samples, a high‑performance engineered metal or alloy, into the Mochii electron microscope to observe space-caused changes to the advanced material’s surface and structure. The physics research work may lead to the development of stronger, lighter, or more durable materials for Earth and space applications.

Flight engineer Sophie Adenot of ESA (European Space Agency) replaced a computer chip inside a research incubator located inside Kibo. Afterward, she updated the incubator’s network settings for the main internal memory chip that performs startup, runs experiments, stores data, and communicates with ground systems.

Roscosmos cosmonauts Sergey Kud-Sverchkov and Sergei Mikaev took turns on Tuesday studying how living in space affects blood pressure. The duo wore a set of cuffs attached to their arms, wrist, and fingers measuring their cardiac data helping doctors keep an eye on crew health and understand how weightlessness affects the circulatory system. Next, they joined Williams and tested the custom-fitted seat liners they will sit in next month when they return to Earth inside the Soyuz MS-28 spacecraft.

Roscosmos flight engineer Andrey Fedyaev spent the first half of his shift inside the Nauka science module working on orbital plumbing and ventilation maintenance. Afterward, Fedyaev cleaned gas-liquid heat exchangers, devices that ensure the space station’s temperature and humidity remain safe and comfortable, inside the Zarya module.

Learn more about station activities by following the space station blog, @space_stationon X, as well as the ISS Facebook and ISS Instagram accounts.

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