NASA astronaut Frank Rubio floats by the International Space Station’s “window to the world.” Yesterday, he returned from the longest single spaceflight by a U.S. astronaut on record - over one year. Exploring deep space will require even longer missions.
Yesterday, NASA astronaut Frank Rubio returned to Earth after over one year, the longest single spaceflight for a U.S. astronaut. But this is just the start; longer and more complex missions into deep space loom ahead, from returning to the moon in 2025 to eventually sending humans to Mars. To ensure that these missions succeed, NASA is increasing efforts to study the biological effects and prevent harm.
The dangers of microgravity are real
A NASA report published in 2016 details a long list of incidents and near-misses caused – at least partly – by space-induced changes in astronauts’ vision and coordination. These issues make it harder to move with precision and to judge distance and velocity.
According to the report, in 1997, a resupply ship collided with the Mir space station, possibly because a crew member bumped into the commander during the final docking maneuver. This mishap caused significant damage to the space station.
Returns to Earth suffered from problems, too. The same report notes that touchdown speeds during the first 100 space shuttle landings were “outside acceptable limits. The fastest landing on record – 224 knots (258 miles) per hour – was linked to the commander’s momentary spatial disorientation.” Earlier, each of the six Apollo crews that landed on the moon had difficulty recognizing moon landmarks and estimating distances. For example, Apollo 15 landed in an unplanned area, ultimately straddling the rim of a five-foot deep crater on the moon, harming one of its engines.
Spaceflight causes unique stresses on astronauts’ brains and central nervous systems. NASA is working to reduce these harmful effects.
NASA
Space messes up your brain
In space, astronauts face the challenges of microgravity, ionizing radiation, social isolation, high workloads, altered circadian rhythms, monotony, confined living quarters and a high-risk environment. Among these issues, microgravity is one of the most consequential in terms of physiological changes. It changes the brain’s structure and its functioning, which can hurt astronauts’ performance.
The brain shifts upwards within the skull, displacing the cerebrospinal fluid, which reduces the brain’s cushioning. Essentially, the brain becomes crowded inside the skull like a pair of too-tight shoes.
That’s partly because of how being in space alters blood flow. On Earth, gravity pulls our blood and other internal fluids toward our feet, but our circulatory valves ensure that the fluids are evenly distributed throughout the body. In space, there’s not enough gravity to pull the fluids down, and they shift up, says Rachael D. Seidler, a physiologist specializing in spaceflight at the University of Florida and principal investigator on many space-related studies. The head swells and legs appear thinner, causing what astronauts call “puffy face chicken legs.”
“The brain changes at the structural and functional level,” says Steven Jillings, equilibrium and aerospace researcher at the University of Antwerp in Belgium. “The brain shifts upwards within the skull,” displacing the cerebrospinal fluid, which reduces the brain’s cushioning. Essentially, the brain becomes crowded inside the skull like a pair of too-tight shoes. Some of the displaced cerebrospinal fluid goes into cavities within the brain, called ventricles, enlarging them. “The remaining fluids pool near the chest and heart,” explains Jillings. After 12 consecutive months in space, one astronaut had a ventricle that was 25 percent larger than before the mission.
Some changes reverse themselves while others persist for a while. An example of a longer-lasting problem is spaceflight-induced neuro-ocular syndrome, which results in near-sightedness and pressure inside the skull. A study of approximately 300 astronauts shows near-sightedness affects about 60 percent of astronauts after long missions on the International Space Station (ISS) and more than 25 percent after spaceflights of only a few weeks.
Another long-term change could be the decreased ability of cerebrospinal fluid to clear waste products from the brain, Seidler says. That’s because compressing the brain also compresses its waste-removing glymphatic pathways, resulting in inflammation, vulnerability to injuries and worsening its overall health.
The effects of long space missions were best demonstrated on astronaut twins Scott and Mark Kelly. This NASA Twins Study showed multiple, perhaps permanent, changes in Scott after his 340-day mission aboard the ISS, compared to Mark, who remained on Earth. The differences included declines in Scott’s speed, accuracy and cognitive abilities that persisted longer than six months after returning to Earth in March 2016.
By the end of 2020, Scott’s cognitive abilities improved, but structural and physiological changes to his eyes still remained, he said in a BBC interview.
“It seems clear that the upward shift of the brain and compression of the surrounding tissues with ventricular expansion might not be a good thing,” Seidler says. “But, at this point, the long-term consequences to brain health and human performance are not really known.”
NASA astronaut Kate Rubins conducts a session for the Neuromapping investigation.
NASA
Staying sharp in space
To investigate how prolonged space travel affects the brain, NASA launched a new initiative called the Complement of Integrated Protocols for Human Exploration Research (CIPHER). “CIPHER investigates how long-duration spaceflight affects both brain structure and function,” says neurobehavioral scientist Mathias Basner at the University of Pennsylvania, a principal investigator for several NASA studies. “Through it, we can find out how the brain adapts to the spaceflight environment and how certain brain regions (behave) differently after – relative to before – the mission.”
To do this, he says, “Astronauts will perform NASA’s cognition test battery before, during and after six- to 12-month missions, and will also perform the same test battery in an MRI scanner before and after the mission. We have to make sure we better understand the functional consequences of spaceflight on the human brain before we can send humans safely to the moon and, especially, to Mars.”
As we go deeper into space, astronauts cognitive and physical functions will be even more important. “A trip to Mars will take about one year…and will introduce long communication delays,” Seidler says. “If you are on that mission and have a problem, it may take eight to 10 minutes for your message to reach mission control, and another eight to 10 minutes for the response to get back to you.” In an emergency situation, that may be too late for the response to matter.
“On a mission to Mars, astronauts will be exposed to stressors for unprecedented amounts of time,” Basner says. To counter them, NASA is considering the continuous use of artificial gravity during the journey, and Seidler is studying whether artificial gravity can reduce the harmful effects of microgravity. Some scientists are looking at precision brain stimulation as a way to improve memory and reduce anxiety due to prolonged exposure to radiation in space.
Other scientists are exploring how to protect neural stem cells (which create brain cells) from radiation damage, developing drugs to repair damaged brain cells and protect cells from radiation.
To boldly go where no astronauts have gone before, they must have optimal reflexes, vision and decision-making. In the era of deep space exploration, the brain—without a doubt—is the final frontier.
Additionally, NASA is scrutinizing each aspect of the mission, including astronaut exercise, nutrition and intellectual engagement. “We need to give astronauts meaningful work. We need to stimulate their sensory, cognitive and other systems appropriately,” Basner says, especially given their extreme confinement and isolation. The scientific experiments performed on the ISS – like studying how microgravity affects the ability of tissue to regenerate is a good example.
“We need to keep them engaged socially, too,” he continues. The ISS crew, for example, regularly broadcasts from space and answers prerecorded questions from students on Earth, and can engage with social media in real time. And, despite tight quarters, NASA is ensuring the crew capsule and living quarters on the moon or Mars include private space, which is critical for good mental health.
Exploring deep space builds on a foundation that began when astronauts first left the planet. With each mission, scientists learn more about spaceflight effects on astronauts’ bodies. NASA will be using these lessons to succeed with its plans to build science stations on the moon and, eventually, Mars.
“Through internally and externally led research, investigations implemented in space and in spaceflight simulations on Earth, we are striving to reduce the likelihood and potential impacts of neurostructural changes in future, extended spaceflight,” summarizes NASA scientist Alexandra Whitmire. To boldly go where no astronauts have gone before, they must have optimal reflexes, vision and decision-making. In the era of deep space exploration, the brain—without a doubt—is the final frontier.
Recent immigration restrictions have left many foreign researchers' projects and careers in limbo—and some in jeopardy.
"I spent about $4,000 on lawyer fees and another $1,200 to pay for the motions I filed," she recalls. "I had to borrow money from my parents and my cousin because without my salary I just didn't have the $7,000 at hand." But the already narrow window of opportunity slammed completely shut when the Trump administration suspended issuing new visas for foreign researchers in June. All Mohan's attempts were denied. In August, she had to leave the country. "Given the recent work visa ban by the administration, all my options in the U.S. are closed," she wrote a bitter note on Twitter. "I have to uproot my entire life in NY for the past 6 years and leave." She eventually found a temporary position in Calcutta, where she can continue research.
Mohan is hardly alone in her visa saga. Many foreign scholars on H- and J-type visas and other permits that let them remain employed in America had been struggling to keep their rights to continue research, which in certain cases is crucial to battling the pandemic. Some had to leave the country, some filed every possible extension to buy time, and others are stuck in their home countries, unable to return. The already cumbersome process of applying for visas and extensions became crippled during the lockdowns. But in June, when President Trump extended and expanded immigration restrictions to cut the number of immigrant workers entering the U.S., the new limits left researchers' projects and careers in limbo—and some in jeopardy.
"We have been a beneficiary of this flow of human capacity and resource investment for many generations—and this is now threatened."
Rakesh Ramachandran, whose computational biology work contributed to one of the first coronavirus studies to map out its protein structures—is stranded in India. In early March, he had travelled there to attend a conference and visit the American consulate to stamp his H1 visa for a renewal, already granted. The pandemic shut down both the conference and the consulates, and Ramachandran hasn't been able to come back since. The consulates finally opened in September, but so far the online portal has no available appointment slots. "I'm told to keep trying," Ramachandran says.
The visa restrictions affected researchers worldwide, regardless of disciplines or countries. A Ph.D. student in neuroscience, Morgane Leroux had to do her experiments with mice at Gladstone Institutes in America and analyze the data back home at Sorbonne University in France. She had finished her first round of experiments when the lockdowns forced her to return to Paris, and she hasn't been able to come back to resume her work since. "I can't continue the experiments, which is really frustrating," she says, especially because she doesn't know what it means for her Ph.D. "I may have to entirely change my subject," she says, which she doesn't want to do—it would be a waste of time and money.
But besides wreaking havoc in scholars' personal lives and careers, the visa restrictions had—and will continue to have—tremendous deleterious effects on America's research and its global scientific competitiveness. "It's incredibly short-sighted and self-destructing to restrict the immigration of scientists into the U.S.," says Benjamin G. Neel, who directs the Laura and Isaac Perlmutter Cancer Center at New York University. "If they can't come here, they will go elsewhere," he says, causing a brain drain.
Neel in his lab with postdocs
(Courtesy of Neel)
Neel felt the outcomes of the shortsighted policies firsthand. In the past few months, his lab lost two postdoctoral researchers who had made major strides in understanding the biology of several particularly stubborn, treatment-resistant malignancies. One postdoc studied the underlying mechanisms responsible for 90 percent of pancreatic cancers and half of the colon ones. The other one devised a new system of modeling ovarian cancer in mice to test new therapeutic drug combinations for the deadliest tumor types—but had to return home to China.
"By working around the clock, she was able to get her paper accepted, but she hasn't been able to train us to use this new system, which can set us back six months," Neel says.
Her discoveries also helped the lab secure about $900,000 in grants for new research. Losing people like this is "literally killing the goose that lays the golden eggs," Neel adds. "If you want to make America poor again, this is the way to do it."
Cassidy R. Sugimoto at Indiana University Bloomington, who studies how scientific knowledge is produced and disseminated, says that scientists are the most productive when they are free to move, exchange ideas, and work at labs with the best equipment. Restricting that freedom reduces their achievement.
"Several empirical studied demonstrated the benefits to the U.S. by attracting and retaining foreign scientists. The disproportional number of our Nobel Prize winners were not only foreign-born but also foreign-educated," she says. Scientific advancement bolsters the country's economic prowess, too, so turning scholars away is bad for the economy long-term. "We have been a beneficiary of this flow of human capacity and resource investment for many generations—and this is now threatened," Sugimoto adds—because scientists will look elsewhere. "We are seeing them shifting to other countries that are more hospitable, both ideologically and in terms of health security. Many visiting scholars, postdocs, and graduate students who would otherwise come to the United States are now moving to Canada."
It's not only the Ph.D. students and postdocs who are affected. In some cases, even well-established professors who have already made their marks in the field and direct their own labs at prestigious research institutions may have to pack up and leave the country in the next few months. One scientist who directs a prominent neuroscience lab is betting on his visa renewal and a green card application, but if that's denied, the entire lab may be in jeopardy, as many grants hinge on his ability to stay employed in America.
"It's devastating to even think that it can happen," he says—after years of efforts invested. "I can't even comprehend how it would feel. It would be terrifying and really sad." (He asked to withhold his name for fear that it may adversely affect his applications.) Another scientist who originally shared her story for this article, later changed her mind and withdrew, worrying that speaking out may hurt the entire project, a high-profile COVID-19 effort. It's not how things should work in a democratic country, scientists admit, but that's the reality.
Still, some foreign scholars are speaking up. Mehmet Doğan, a physicist at University of California Berkeley who has been fighting a visa extension battle all year, says it's important to push back in an organized fashion with petitions and engage legislators. "This administration was very creative in finding subtle and not so subtle ways to make our lives more difficult," Doğan says. He adds that the newest rules, proposed by the Department of Homeland Security on September 24, could further limit the time scholars can stay, forcing them into continuous extension battles. That's why the upcoming election might be a turning point for foreign academics. "This election will decide if many of us will see the U.S. as the place to stay and work or whether we look at other countries," Doğan says, echoing the worries of Neel, Sugimoto, and others in academia.
Dogan on Zoom talking to his fellow union members of the Academic Researchers United, a union of almost 5,000 Academic Researchers.
(Credit: Ceyda Durmaz Dogan)
If this year has shown us anything, it is that viruses and pandemics know no borders as they sweep across the globe. Likewise, science can't be restrained by borders either. "Science is an international endeavor," says Neel—and right now humankind now needs unified scientific research more than ever, unhindered by immigration hurdles and visa wars. Humanity's wellbeing in America and beyond depends on it.
[Editor's Note: To read other articles in this special magazine issue, visit the beautifully designed e-reader version.]