UPDATE: Three astronauts from Expedition 73 are set to undock from the International Space Station (ISS) at 8:41 p.m. EDT today, December 8, 2025, marking the end of their 245-day mission in orbit. NASA astronaut Jonny Kim and Russian cosmonauts Sergey Ryzhikov and Alexey Zubritsky will return to Earth just hours later, with landing scheduled for 12:04 a.m. EDT on December 9 in Kazakhstan.
As the crew prepares for their departure, urgent blood research is taking precedence aboard the ISS. This vital work ensures the health of astronauts living long-term in microgravity. Today, the team practiced critical operations inside the Soyuz MS-27 spacecraft, where they will experience the intense pull of Earth’s gravity during reentry.
In a remarkable effort to combat space-related health issues, Ryzhikov and Zubritsky tested a unique suit designed to counteract fluid shifts that occur in microgravity. This innovative suit pulls blood toward the feet, potentially preventing head and eye pressure experienced by astronauts in space, and easing their transition back to gravity.
Meanwhile, NASA Flight Engineers Zena Cardman and Chris Williams conducted vital cardiovascular research. Using the Ultrasound 2 device, they scanned their veins and measured blood pressure, providing crucial data on astronaut health before, during, and after missions. Their findings are part of the ongoing CIPHER investigation, which examines how spaceflight impacts the human body.
Earlier today, Flight Engineers Mike Fincke of NASA and Kimiya Yui of JAXA helped familiarize Williams with life aboard the ISS. Williams joined the station on November 27, 2025, and is currently adjusting to the complexities of orbital life.
The urgency of these research activities highlights the ongoing commitment to astronaut health, especially as the crew prepares for their return. As they wrap up their mission, the team is also engaging in life support maintenance and documenting supplies on the station.
NASA will provide live coverage of the crew’s return, accessible via NASA+, Amazon Prime, and the agency’s YouTube channel. This mission, which has pushed the boundaries of space exploration, underscores the importance of understanding human physiology in space and the challenges astronauts face during extended missions.
Stay tuned as we follow this developing story and the return of these brave astronauts. For continuous updates, follow the ISS blog or check out @space_station on X, along with the ISS Facebook and Instagram channels.
