Circadian Rhythms: A crewmember removed the Armband Monitor and the Thermolab Unit mounted to their belt, completing 36 hours of monitoring for the Circadian Rhythms investigation. Circadian Rhythms investigates the role of synchronized circadian rhythms, or the “biological clock,” and how it changes during long-duration spaceflight. Researchers hypothesize that a non-24-hour cycle of light and …