Scientists Figure Out Why Many Returning Astronauts Need Glasses

NASA
NASA

The zero-G lifestyle does funny things to our bodily fluids. That’s the conclusion of one recent study, which may have found a reason for a common space travelers’ malady. The researchers presented their results [PDF] at the annual meeting of the Radiological Society of North America.

If we’re going to start sending humans to Mars and other distant destinations, we’re going to need to know if we can survive the trip. So astronauts are an incredible scientific resource, not only for what they do while in space, but also for what they experience. Living in orbit can shrink astronauts’ hearts and stretch their spines. It can also damage their ability to see: Numerous travelers who left Earth with 20/20 vision have returned to find they need glasses just to read or drive.

"People initially didn't know what to make of it, and by 2010 there was growing concern as it became apparent that some of the astronauts had severe structural changes that were not fully reversible upon return to earth,” lead author Noam Alperin of the University of Miami said in a statement.

Scientists call the phenomenon visual impairment intracranial pressure, or VIIP. The name is slightly misleading in its certainty. Researchers think the eye problems are the result of increased pressure inside astronauts’ heads, but they haven’t really been sure.

Alperin and his colleagues wondered if the problem might not be liquid—cerebrospinal fluid (CSF), to be precise. CSF is a crucial component of healthy brain and body function. It surrounds our brains and spinal cords and acts kind of like amniotic fluid in the womb, ensuring a flow of nutrients and removing waste. CSF is also somewhat adaptable and responds to changes in the position and angle of your body and head. It’s a good system, and it works.

At least where there’s gravity. The research team scanned the brains and eyeballs of seven different astronauts both before and after long stints aboard the International Space Station (ISS). They compared those scans with results from another nine astronauts who had only been on the ISS briefly.

There could be no doubt about it—longer stays in space were messing with the astronauts’ eyes. Their eyes were more flattened; their optic nerves showed more swelling; and, most interestingly, they had higher volumes of CSF in their eye sockets and in the CSF-producing part of the brain. The higher the CSF volume, the more trouble an astronaut had seeing.

"The research provides, for the first time, quantitative evidence obtained from short- and long-duration astronauts pointing to the primary and direct role of the CSF in the globe deformations seen in astronauts with visual impairment syndrome," Alperin said.

Identifying the source of the problem is the first step to correcting it. Alperin and NASA are now working to simulate the conditions that cause VIIP so they can figure out how to protect astronauts’ eyes in the future.

These Rugged Steel-Toe Boots Look and Feel Like Summer Sneakers

Indestructible Shoes
Indestructible Shoes

Thanks to new, high-tech materials, our favorite shoes are lighter and more comfortable than ever. Unfortunately, one thing most sneakers are not is durable. They can’t protect your feet from the rain, let alone heavy objects. Luckily, as their name implies, Indestructible Shoes has come up with a line of steel-toe boots that look and feel like regular sneakers.

Made to be incredibly strong but still lightweight, every pair of Indestructible Shoes has steel toes, skid-proof grips, and shock-absorption technology. But they don't look clunky or bulky, which makes them suitable whether you're going to work, the gym, or a family gathering.

The Hummer is Indestructible Shoes’s most well-rounded model. It features European steel toes to protect your feet, while the durable "flymesh" material wicks moisture to keep your feet feeling fresh. The insole features 3D arch support and extra padding in the heel cup. And the outsole features additional padding that distributes weight and helps your body withstand strain.

Indestructible Shoes Hummer.
The Hummer from Indestructible Shoes.
Indestructible Shoes

There’s also the Xciter, Indestructible Shoes’s latest design. The company prioritized comfort for this model, with the same steel toes as the Hummer, but with additional extra-large, no-slip outsoles capable of gripping even smooth, slippery surfaces—like, say, a boat deck. The upper is made of breathable moisture-wicking flymesh to help keep your feet dry in the rain or if you're wearing them on the water.

If you want a more breathable shoe for the peak summer months, there's the Ryder. This shoe is designed to be a stylish solution to the problem of sweaty feet, thanks to a breathable mesh that maximizes airflow and minimizes sweat and odor. Meanwhile, extra padding in the midsole will keep your feet protected.

You can get 44 percent off all styles if you order today.

This article contains affiliate links to products selected by our editors. Mental Floss may receive a commission for purchases made through these links.

NASA Names Washington, D.C., Headquarters After ‘Hidden Figure’ Mary Jackson

Mary W. Jackson at NASA in 1980.
Mary W. Jackson at NASA in 1980.
Adam Cuerden, NASA Langley Research Center, Wikimedia Commons // Public Domain

In the past, NASA’s headquarters building in Washington, D.C., was simply known as “NASA Headquarters” or “Two Independence Square” (the name of that particular piece of real estate). This week, the agency officially named it the “Mary W. Jackson NASA Headquarters,” after NASA’s first Black female engineer.

Jackson worked as a math teacher and U.S. Army Secretary before NASA—called the National Advisory Committee for Aeronautics at the time—recruited her as a research mathematician for its segregated West Area Computing Unit in 1951. After completing a training program in 1958 (which she needed special permission to attend, since it took place at a whites-only high school), she was promoted to engineer.

In the following decades, Jackson studied wind tunnels and air behavior around aircraft, and she was also instrumental in helping the U.S. pull forward in the Space Race of the 1960s. But Jackson’s legacy goes beyond her own engineering efforts: Between 1979 and 1985, she participated in the Federal Women’s Program at NASA’s Langley Research Center, where she advocated for the hiring and promotion of more female scientists.

mary jackson with young female scientists in 1983
Jackson with a group of young scientists and mathematicians in 1983.

“Mary W. Jackson was part of a group of very important women who helped NASA succeed in getting American astronauts into space,” NASA administrator Jim Bridenstine said in a press release. “Mary never accepted the status quo; she helped break barriers and open opportunities for African Americans and women in the field of engineering and technology.”

Jackson died in 2005, and her story was largely unknown until the release of Margot Lee Shetterly’s 2016 book Hidden Figures and subsequent film of the same name, which chronicled the contributions of Jackson and her colleagues Katherine Johnson, Dorothy Vaughan, and Christine Darden. In 2019, Congress passed a bipartisan bill to rename the part of E Street SW where NASA’s headquarters is located to Hidden Figures Way, and the women were also awarded Congressional Gold Medals.

NASA headquarters
The Mary W. Jackson NASA Headquarters in Washington, D.C.

“We are honored that NASA continues to celebrate the legacy of our mother and grandmother Mary W. Jackson,” Jackson’s daughter Carolyn Lewis said in the press release. “She was a scientist, humanitarian, wife, mother, and trailblazer who paved the way for thousands of others to succeed, not only at NASA, but throughout this nation.”