Expedition 73 Flight Engineers Chris Williams and Jonny Kim

iss073e1228220 (Dec. 2, 2025) --- Expedition 73 Flight Engineers (from left) Chris Williams and Jonny Kim, both NASA astronauts, work together inspecting and cleaning the Enhanced European Exploration Exercise Device (E4D) inside the International Space Station's Columbus laboratory. The E4D is being tested on the orbital outpost for its ability to provide bicycling, rowing, and resistance exercises to protect a crew member’s muscles, bones, and heart health in microgravity.