3rd September 2023,Mumbai: Understanding Circadian Rhythm
European Space Agency astronaut Andreas Mogensen is conducting sleep-related experiments on the International Space Station (ISS). Have you ever been told to avoid looking at your phone before bedtime? That’s because the blue light emitted by screens can disrupt your Circadian rhythm, your body’s natural response to daylight changes. Now, to understand this, the European Space Agency (ESA) astronaut Andreas Mogensen, currently on the Huginn mission aboard the International Space Station (ISS), is engaged in two sleep-related experiments: Circadian Light and Sleep in Orbit. These experiments address the challenges of maintaining a natural daily rhythm in space, where astronauts witness 16 sunsets and sunrises every day due to the ISS’s rapid orbit around Earth.
What is Circadian Rhythm?
Circadian rhythm, according to ESA, is the physical, mental, and behavioral changes our bodies undergo over a period of about 24 hours. Our internal clock is linked to the body’s core temperature, which varies throughout the day and triggers our metabolism and sleep cycle. “Light exposure is obviously a factor influencing our rhythm as humans tend to wake up during the day and sleep at night,” ESA notes.
The Circadian Light Experiment
To combat this disorienting phenomenon, Andreas is testing the Circadian Light Panel, a custom lamp developed by Danish company SAGA Space Architects. This lamp emits light spectra resembling natural circadian rhythms, assisting Andreas in regulating his circadian rhythm. “In the evening, when Andreas goes to sleep, the light will glow in red to simulate a calming sunset. In the morning, when Andreas wakes up, the light will turn blue, evoking the colors of a morning sky,” ESA informed. Maintaining a natural circadian rhythm is vital for astronauts’ well-being, as the ISS follows Greenwich Mean Time (GMT) to maintain a consistent schedule. The space station’s unique routine can disrupt the internal body clock, which is closely linked to core body temperature, metabolism, and the sleep cycle.
Sleeping in Orbit: Monitoring Brain Activity
Furthermore, researchers from Aarhus University in Denmark have equipped Andreas with an in-ear measuring device, similar to headphones, to monitor his brain’s electroencephalogram (EEG) patterns during sleep. This device aims to provide insights into the quality of sleep experienced by astronauts in space. The aim of these experiments is “to gain knowledge of the way the conditions in space and on the ISS affect astronauts, and how this understanding can be used for the benefit of human health here on earth.”
Challenges of Life on the ISS
Life on the ISS presents numerous challenges, and one of the most significant is adapting to a schedule that sees 16 sunrises and sunsets in a single day. This constant change in light and darkness can wreak havoc on an astronaut’s internal body clock. Maintaining a regular sleep pattern becomes particularly challenging, as the absence of natural sunlight cues makes it difficult for astronauts to differentiate between day and night.
The Importance of Circadian Rhythm
Circadian rhythm is crucial for overall health and well-being. It regulates not only our sleep patterns but also our metabolism, hormone production, and various bodily functions. Disruptions to the circadian rhythm can lead to sleep disorders, mood disturbances, and even impact physical health. For astronauts, whose physical and mental health is paramount during missions, understanding and preserving circadian rhythm is essential.
The Science Behind Circadian Light
The Circadian Light experiment takes a scientific approach to address this issue. By using specially designed lighting that mimics the natural progression of light throughout the day, astronauts like Andreas Mogensen can regulate their circadian rhythms more effectively. The red light simulating sunset in the evening helps prepare the body for sleep, while the blue light resembling a morning sky promotes alertness upon waking.
Monitoring Astronauts’ Sleep Quality
The Sleep in Orbit experiment, equipped with the in-ear EEG monitoring device, offers valuable insights into the sleep quality of astronauts in space. Sleep is essential for cognitive functioning, mood stability, and overall health. Understanding how the space environment impacts sleep patterns and quality is critical for ensuring the well-being and performance of astronauts during extended missions.
Applications Beyond Space
While these experiments are conducted in the unique environment of space, their findings have implications far beyond the ISS. The knowledge gained from studying circadian rhythms and sleep patterns in space can be applied to improving sleep health on Earth. Shift workers, individuals with sleep disorders, and anyone seeking better sleep could benefit from the insights gained through these experiments. Andreas Mogensen’s sleep-related experiments on the ISS shed light on the challenges astronauts face in maintaining a natural daily rhythm in space. By exploring circadian rhythms and sleep quality, scientists are not only improving the well-being of astronauts but also contributing to our understanding of sleep on Earth. These experiments serve as a reminder of the vital importance of circadian rhythm and quality sleep for human health, both in the cosmos and on our home planet.
-by Kashvi Gala