Expedition 73 marked a busy day aboard the International Space Station as a SpaceX Dragon performed a reboost demo, researchers advanced a study of bone stem cells, and astronauts deployed Axiom Space’s first on-orbit data center hardware. The combined operations highlight the station’s role as a platform for orbital logistics, human health research, and in-space computing.
Dragon reboost demonstration
A SpaceX Dragon cargo spacecraft executed a station reboost using an external reboost kit mounted in its trunk. The independent propellant system powered two Draco engines for several minutes to demonstrate capability to adjust the ISS’s altitude, which is periodically required to counter atmospheric drag and optimize orbital parameters for visiting vehicles.
Biomedical research in Kibo
NASA Flight Engineer Jonny Kim processed bone stem cell samples inside the Kibo laboratory’s Life Science Glovebox to study molecular changes to the skeletal system in microgravity. Human-derived samples delivered by Dragon are being treated with a therapeutic agent to better characterize spaceflight-induced bone loss. After incubation, specimens are preserved in a science freezer for return on a future Dragon splashdown, enabling detailed analysis on Earth.
Technology and manufacturing payloads
JAXA astronaut Kimiya Yui prepared an artificial gravity-generating incubator to investigate fermentation and brewing processes using sake yeast, supporting broader studies of microbial behavior and bioprocessing in space. Yui also installed the Axiom Data Center Unit-1 in the Destiny lab to evaluate on-orbit data processing, storage, and potential support for advanced manufacturing applications.
Cargo operations and systems work
NASA astronauts Zena Cardman and Mike Fincke continued unpacking science and hardware from Dragon and reorganized stowage in the Permanent Multipurpose Module. Cardman serviced the cupola robotics workstation, while Fincke reviewed procedures and gathered equipment for an upcoming physics investigation aimed at developing new materials, including pharmaceuticals, in microgravity.
Safety training and station maintenance
Station Commander Sergey Ryzhikov and Flight Engineer Alexey Zubritsky, together with Kim, rehearsed an emergency evacuation drill to quickly board Soyuz MS-27 and undock if required. Roscosmos cosmonaut Oleg Platonov documented daily activities and performed ventilation maintenance in the Nauka module.
Why it matters
- Orbital logistics: A successful Dragon reboost demonstration adds flexibility for maintaining station altitude.
- Human health: Bone stem cell research targets countermeasures for long-duration missions.
- In-space computing: Axiom’s data center unit explores processing and storage closer to where data is generated.
- Industrial R&D: Microgravity bioprocessing and materials science support future commercial applications.
Source: NASA ISS Blog
