With 16 sunrises every 24 hours, how do astronautson the space station get a decent night’s sleep? And how can they dodge disorders and diseases linked to disrupted sleep, such as cardiovascular diseases and some types of cancers?
These questions – and more – are being explored by those living on the space station and researchers on the ground below. Finding answers could help not only future space station missions, but also shift workers and people who regularly cross time zones.
A person’s natural sleep/wake cycle is regulated by his or her circadian rhythm. If this is disturbed, though, people can become fatigued and unwell.
So NASA’s flight surgeons and scientists devised tools for those on the space station and in mission control, which often involves shift work, to help keep a more natural circadian rhythm.
Schedule sleep and wake times
Allowing the body time to prepare for situations where circadian misalignment may occur is the most effective countermeasure against sleep problems like insomnia and fatigue.
Sleep education and training
Being aware of what factors impact sleep quality and quantity is important for promoting healthy sleep hygiene, or the behaviours, environmental conditions and other sleep-related factors that can affect sleep.
Sleep environment
Every effort is made to provide space station crew members a sleeping environment that encourages healthy, undisrupted sleep times.
Light control
Lighting on the station is being transitioned from general luminaire assemblies to solid-state light assemblies, which allow crew members to adjust the colour spectrum and intensity of the light to promote alertness and circadian resetting, or to promote sleep. Se the power of light in the video above.
Non-prescription sleep and alertness substances
Melatonin and caffeinated products may be used to address circadian rhythm disruptions.
Sleep cognitive behavioural therapy
Sleep cognitive behavioural therapy provides a solution to the random, unwanted thoughts that tend to cloud the mind just before bedtime and lead to the inability to naturally transition to sleep.
Drug interventions
Once a crew member has exhausted the aforementioned options for successful circadian shifting techniques, options for pharmacological interventions are explored.
For more, check out NASA’s list of human research projects running on the space station.