SAGA specializes in research and design for future space habitation. With the goal of developing the best Moon habitat for humans, not just trained astronauts, SAGA launched LUNARK – a simulated Moon habitat for research, with the aim that it one day can sustain life on the Moon. Part of their research was on circadian rhythm and lighting’s impact on wellbeing. They partnered with Louis Poulsen to develop special lighting panels for their research.
From September to November 2020, LUNARK, the deployable habitat, was tested on an analog Moon mission near Moriusaq, Greenland in the high Arctic. Sebastian Aristotelis and Karl-Johan Sørensen from SAGA deployed the habitat and lived in it for 60 days, completely isolated. During the expedition, the habitat sustained a comfortable living environment while enduring Hurricane scale winds, snow-storms, and temperatures down to -30°C.
A key factor for psychological and physical well-being is the need for a stable circadian rhythm, which the Moon lacks due to its 28 day-night cycle. In partnership with Louis Poulsen, SAGA created custom-made Circadian Light Panels to bathe the interiors in pseudo-natural daylight, accurately emulating the subtle hourly variations of natural daylight on Earth. The circadian lighting system in the habitat is a completely automated system developed to aid in human well-being in extreme environments. Sleep disruptions and out-of-sync circadian rhythms make astronauts lethargic and unproductive. The Circadian Light Panels on the ceiling simulate varying weather and daylight conditions. There were two challenges to solve with the Circadian Light Panels – stimuli and circadian rhythm.
In space, every day is the same, your senses become numb, your cognitive abilities deteriorate. You quickly start to lose your sense of time. The Circadian Light Panels combat this by adding variation, by emulating the daily cycle of natural sunlight. SAGA simulated all the phases of a natural light environment: dawn, sunrise, daylight, sunset and dusk. To combat monotony even further, the panels were also programmed with variation between the days to mimic various weather patterns we experience on Earth, from overcast and low light intensity to brighter, high intensity warm light.
A healthy circadian rhythm is one of the most impactful ways to maintain good well-being. On the Moon, this is challenged as the sunlight environment is very different. If you are at the equator of the Moon, you’ll experience 14 days of sunlight followed by 14 days of darkness; at the south pole of the Moon, there’s almost always sunlight. The crew of LUNARK experienced similarly difficult light conditions by being close to Earth’s North Pole in the Arctic circle. Simulating a healthy circadian rhythm stimulates natural sleep and wake hormone production in the body. Lowering the intensity of blue light towards the evening promotes production of the sleep hormone melatonin production, and likewise waking up to increasing blue light suppresses melatonin and promotes cortisol.