The actigraphy device that select Artemis II astronauts will wear on their wrists during their mission around the Moon. The device will measure the crew members’ motion, sleep patterns, and exposure to light as part of the ARCHeR (Artemis Research for Crew Health and Readiness) study. What we learn will help us understand how astronauts can ultimately survive and thrive on longer duration missions farther from Earth. Credit: NASA/Helen Arase Vargas
Photographer Helen Arase Vargas NASA-JSC
Date September 17, 2025