Crew Handover Underway as Expedition 74 Nears End

The three Expedition 74 crew members who launched aboard Soyuz MS-28 last November are now packing cargo and transferring duties ahead of their parachute-assisted landing in Kazakhstan this weekend. NASA astronaut Chris Williams is handing over responsibilities to newly arrived flight engineer Anil Menon, who flew in on Soyuz MS-29 on July 14 alongside Roscosmos cosmonauts Pyotr Dubrov and Anna Kikina. The departing crew’s undocking signal the start of Expedition 75, with NASA’s Jessica Meir assuming command.

Alongside the logistical choreography, Williams has been guiding Menon through the station’s layout, medical supply locations, and the operation of laboratory hardware. Meanwhile, Kud-Sverchkov and Mikaev continued testing an experimental lower body negative pressure suit. The suit is designed to counteract the headward fluid shift caused by weightlessness, helping crew members readjust to Earth’s gravity more quickly after months in space.

The incoming crew – Menon, Dubrov, and Kikina – are transitioning from orientation to full-time research. Menon began the week with blood draws, blood pressure checks, and arterial scans using an ultrasound device. Dubrov and Kikina separately donned virtual reality goggles to complete tests of balance and spatial orientation, part of ongoing studies into how the nervous system adapts to microgravity. The data gathered will inform medical strategies to keep astronauts healthy on long-duration missions.

Why This Rotation Matters for Space Research

The Lower Body Negative Pressure Suit and Human Adaptation

The lower body negative pressure suit being tested by the Russian crew is not merely a comfort tool; it addresses a fundamental physiological challenge of spaceflight. In microgravity, fluids shift from the lower body toward the head, contributing to facial puffiness, nasal congestion, and altered blood pressure regulation. By applying negative pressure around the legs, the suit helps pull fluids back downward, potentially reducing orthostatic intolerance – the dizziness or fainting some astronauts experience after landing. Data from these tests could directly influence countermeasure protocols for future missions to the Moon or Mars, where astronauts will need to perform effectively immediately after long periods in weightlessness.

Leadership Transition and Crew Continuity

The rotation also marks a change in station command, with Jessica Meir set to lead Expedition 75. Command transitions are carefully choreographed to preserve operational stability. Williams’ handover to Menon goes beyond inventory management; it includes tacit knowledge transfer about system quirks and emergency procedures. The fact that both the departing and arriving crews overlap for about a week ensures a reservoir of experience remains aboard, a practice that has become standard since the ISS was permanently occupied. This continuity is especially important as the station supports a growing array of international experiments, many of which require precise execution of multi-week protocols.