- BBC News World
Scientists have developed a high-tech sleeping bag that could prevent vision problems that some astronauts experience while living in space.
In zero gravity, fluid floats on the head and crushes the eyeball over time.
This is one of the most serious problems for astronauts, and some experts worry it could jeopardize missions to Mars.
her bags Technology that absorbs fluids from head to toe.
The person responsible for its development is Benjamin LevineD., professor of internal medicine at the University of Texas Southwestern Medical Center, who is seeking to use the device on the International Space Station (ISS).
NASA has documented vision problems in more than half of the astronauts working on the International Space Station. Some became farsighted, had difficulty reading, and sometimes needed support from other members of the same crew to complete pilot assignments.
“We don’t know how severe the effects will be on a longer flight, such as the two-year process of Mars,” said Professor Levine, who is also director of the Institute for Environmental Medicine and Exercise, a program at Southwestern Medical. The center is in association with Texas Health Presbyterian Hospital in Dallas.
“It would be a huge disaster if the astronauts were so disabled that they wouldn’t be able to see what they were doing, and that would jeopardize the mission,” he added.
In 2005, astronaut John Phillips launched himself to the International Space Station with 20/20 vision and returned six months later with 20/100 vision. Others suffer from a less severe version of the condition.
On Earth, when a person gets out of bed, gravity causes fluids to flow into the body, which is known as “discharge.” However, in space, low gravity allows approximately two liters of body fluid to accumulate in the head, putting pressure on the eyeball.
Being in space can cause a disease called spaceflight-associated neurological eye syndrome (SANS), which causes progressive flattening of the back of the eye, optic neuritis, and double vision.
How does a sleeping bag work?
Although the brain pressure of a person lying on Earth is slightly higher than that of a person in space, when they stand up, they dilute, which is never the case with astronauts in zero gravity.
The sleeping bag, co-developed with outdoor equipment manufacturer REI, fits a person’s waist, encircling the lower body with a rigid frame.
Hence, the suction device, which works on the same principle as a vacuum cleaner, creates a pressure difference that pulls the liquid towards the feet. This prevents it from accumulating in the brain and creating harmful pressure on the eyes.
Before using this new technology routinely, it is necessary to check the time that astronauts should spend with the sleeping bag.
Dr. Levine asked, “Does everyone need to do this or is it just the people at risk of developing SANS? Do they need to do this once they are in space, or can they wait and see if their vision changes?” .
Despite these questions, the scientist was optimistic that SANS would not pose a health risk when NASA begins missions to Mars.
How did they test the technology?
Twelve cancer survivors helped explain the causes of this condition. The study volunteers had outlets in their heads for chemotherapy and allowed experts to measure their brain pressure while flying in equivalent zero-gravity flights for several seconds.
In this way, the scientists took the measurements while lying down with or without a sleeping bag. The researchers found that during just three days of lying down they had pressure that slightly changed the shape of the eyeball, but no such change occurred when the suction technique was used.
The bag technique can also help improve a condition called microgravity-induced atrial fibrillation, which causes the heart to contract in space, thus beating irregularly.
The work has been reviewed by the magazine Gamma Ophthalmology.
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