Two Roscosmos Cosmonauts Complete First Extravehicular Activity of Expedition 73
Two Russian cosmonauts returned inside the International Space Station after a six-hour EVA that combined the installation of a cutting-edge semiconductor materials experiment with the disposal of a legacy piece of equipment. Expedition 73 commander Sergey Ryzhikov and flight engineer Alexey Zubritsky, both affiliated with Roscosmos, wrapped up their spacewalk at 7:19 p.m. EDT (23:19 GMT) after beginning their excursion at 1:10 p.m. EDT (17:10 GMT).
Installing the Molecular Beam Epitaxy Experiment
The crew’s first objective was to advance materials science in microgravity. Ryzhikov handled the Ekran-M instrument, a Molecular Beam Epitaxy experiment, while positioned at the end of the European Robotic Arm (ERA). The ERA is operated remotely from the station, with control from a workstation inside the ISS managed by cosmonaut Oleg Platonov who guided the arm during the operation.
Once at the Nauka multipurpose laboratory module’s exterior, Ryzhikov and Zubritsky configured the equipment, routed power cables, and mounted a swappable cassette for ongoing experiments. The goal of the Ekran-M setup is to grow and study ultra-thin materials that are difficult to produce on Earth due to gravity and related limitations. By leveraging the microgravity environment of space, researchers aim to push the boundaries of materials science and potentially unlock new semiconductor applications for Earth and space-based technologies.
Disposing of a No-Longer-Needed HDTV Camera
With their primary task complete, the duo moved to the Zvezda service module to retrieve and jettison a high-definition television system once part of a Canadian commercial payload. Zubritsky positioned himself at the end of the European Robotic Arm and released the camera into space, sending a final update: “Jettison is complete.” The discarded hardware, weighing about 180 pounds (82 kilograms) and measuring roughly 2 by 4.6 by 2.3 feet (0.6 by 1.4 by 0.7 meters), is expected to reenter Earth’s atmosphere and burn up as it reenters the atmosphere, far from populated areas.
The jettisoned camera’s removal minimizes debris risk and aligns with routine maintenance aboard the orbiting outpost. Internal communications captured the team’s calm and efficient progress as they completed the task and prepared to relocate back toward the Poisk module.
Window Cleaning and Material Return
After completing the camera work, Ryzhikov and Zubritsky turned their attention to routine maintenance, cleaning a window on the Zvezda service module. This task helps maintain visibility for external operations and ensures ongoing integrity of the station’s external surfaces. The EVA also included gathering exposed material samples as part of a separate materials experiment, with the astronauts collecting the items to bring back inside the station for analysis.
Implications for Future Missions
Today’s activities highlight the evolving role of international collaborations in space. The Ekran-M experiment represents ongoing efforts to advance semiconductor materials research in space, potentially informing future manufacturing processes for electronics used on spacecraft and in terrestrial technologies. The successful jettison demonstrates rigorous debris management practices essential to long-duration human spaceflight, drastically reducing orbital debris and preserving operations for both current and future crews.
What’s Next for Expedition 73
With both cosmonauts back inside the Poisk module, the crew will likely debrief and prepare for subsequent tasks as part of Expedition 73’s ongoing mission schedule. The operations underscore the ISS’s continuing role as a platform for high-profile research and international cooperation, where microgravity science, engineering demonstrations, and space architecture all advance in concert.
