The seven members of the Expedition 74 crew studied stem cells, packed up a cargo ship and maintained their toilet this week, Dec. 8-12, 2025, on board the International Space Station (ISS).
Orbital observation
“Thinking, ‘I’m sure everyone would want to see a photo of Earth,’ I took a few shots right before going to bed. I think the amazing thing about the ISS is that you can see views like this without even trying,'” JAXA astronaut Kimiya Yui, an Expedition 74 flight engineer, wrote on social media on Thursday (Dec. 11).
Yui’s photo nicely captures the “skies of blue and clouds of white” as sung by the iconic Louis Armstrong.
Science status
Among the research that was conducted by the Expedition 74 crew aboard the space station this week was:
StemCellEx-IP1 — In an effort that may someday lead to ways to repair damaged organs and tissue, NASA astronaut Zena Cardman studied stem cells under a microscope, observing their production in microgravity as compared to on Earth.
Virtual — In a Roscosmos experiment that looks at how the vestibular system adapts to microgravity, Sergey Kud-Sverchkov and Sergei Mikaev traded off wearing a different set of VR (virtual reality) goggles to track their vision. The study could lead to developing additional countermeasures when readjusting to gravity.
Station keeping
The Expedition 74 crew also devoted time to maintaining the space station’s systems, including:
JEM DRCS — In a demo that has applications to future Artemis missions to the moon and ultimately to Mars, JAXA astronaut Kimiya Yui installed and soundproofed the JEM Demonstration of CO2 Removal System in the station’s Kibo module. The experimental device traps carbon dioxide from the air and vents it overboard.
JAXA’s HTV-X1 — NASA astronauts Chris Williams and Mike Fincke, together with some help from Zena Cardman and JAXA astronaut Kimiya Yui, continued preparing the cargo ship for its departure in January. Williams worked on loading refuse and no-longer-needed equipment, while Fincke focused on preparing a science rack for its transfer from the space station to inside the HTV-X.
Waste and Hygiene Compartment — Fincke also spent some of his time this week servicing one of the space station’s restrooms, replacing orbital plumbing components in the Tranquility node.
Astronaut activity
NASA astronaut Chris Williams is living out his boyhood dream as an Expedition 74 flight engineer.
“For as far back as I can remember, so when I was a little kid, I was always fascinated by exploration and in particular, space,” said Williams. “I think it is one of those things that a lot of kids have a fascination with, and I just never grew out of it. It is something that has always been a point of curiosity for me, and being an astronaut felt like the best way to explore space.”
Williams discussed his path to flying in space and serving aboard the International Space Station during an in-flight interview on Thursday (Dec. 11), with The Washington Post. You can watch the full discussion in the video above.
By the numbers
As of Friday (Dec. 12), there are 7 people aboard the International Space Station: Expedition 74 commander Mike Fincke and Zena Cardman and Chris Williams of NASA; JAXA (the Japan Aerospace Exploration Agency) astronaut Kimiya Yui; Oleg Platonov, Sergey Kud-Sverchkov and Sergey Mikaev of Roscosmos, all flight engineers.
There are two docked crew spacecraft: SpaceX‘s Dragon “Endeavour” attached to the space-facing port of the Harmony module and Roscosmos’ Soyuz MS-28 attached to the Earth-facing port of the Rassvet module.
There are four cargo spacecraft: Roscosmos’ Progress MS-31 (92P) docked to the space-facing port of the Poisk module, Progress MS-32 (93P) attached to the aft port of the Zvezda service module, Northrop Grumman’s Cygnus XL, the S.S. William C. “Willie” McCool, berthed to the Earth-facing common berthing mechanism (CBM) on the Unity node and Japan’s HTV-X1 attached to the Earth-facing CBM on the Harmony node.
As of Friday, the space station has been continuously crewed for 25 years, 1 month and 10 days.