Crew Rotation Marks End of Expedition 74

Three Expedition 74 crew members are in their final days aboard the International Space Station. NASA astronaut Chris Williams and Roscosmos cosmonauts Sergey Kud-Sverchkov and Sergei Mikaev will board the Soyuz MS-28 spacecraft on Sunday, July 26, and undock from the Rassvet module at 3:02 a.m. EDT, with a parachute-assisted landing in Kazakhstan expected at 6:26 a.m. EDT (3:26 p.m. local time). Their return will conclude an eight-month science and maintenance mission.

The trio is spending their remaining time packing cargo and handing over responsibilities to their replacements. The formal end of Expedition 74 and start of Expedition 75 occurs at the moment of undocking. Meanwhile, the rest of the crew—including newly arrived flight engineers—continues a full slate of experiments, from blood sample collection to spacesuit checks, ensuring zero interruption to research.

NASA flight engineer Anil Menon set up research incubators in the Columbus module, while Roscosmos’s Pyotr Dubrov and Ana Kikina processed blood samples for stowage in a science freezer. In the Quest airlock, NASA’s Jack Hathaway and ESA’s Sophie Adenot reviewed procedures and inspected spacesuits, and later Hathaway replaced orbital plumbing components in the Tranquility module. Adenot also recorded herself exercising on the new European Enhanced Exploration Exercise Device, footage that will help refine workout techniques for future deep-space missions.

Why This Routine Handover Matters for Space Station Operations

Routine Rotation, Uninterrupted Research

The crew handover is a standard feature of orbital operations, but it illustrates the precision of international cooperation required to keep the space station continuously inhabited. Because return slots and launch windows are tightly choreographed months in advance, even minor delays can cascade through visiting vehicle schedules. The current plan, with the Soyuz departing just days after the new crew’s arrival, keeps occupancy steady at seven people and avoids gaps in laboratory work.

No experiments are paused. The incoming crew members immediately picked up tasks—blood draws, incubator setups, spacesuit maintenance—demonstrating that operational knowledge transfer is swift and that the station never stops functioning as a working laboratory. The European exercise device test signals ongoing preparation for the Artemis program and potential lunar and Martian missions, where maintaining muscle and bone health will be critical.

Geopolitical Steady State

Despite terrestrial tensions between the U.S. and Russia, the space station partnership continues to operate on a business-as-usual basis. Russian Soyuz vehicles remain a reliable crew transport alongside the U.S. commercial crew program. The rotation underscores that life-support and research systems are managed jointly, with no visible impact from political disputes on daily station activities.