How Healthy Do I Need to Be Before Heading to Space?6 min read

Astronaut to Mission Control: Houston, I think we have a problem. My blood pressure is a little bit high today.

Let’s chalk this exchange up to “things you don’t see in the movies.” Though, since astronauts in space don’t have the luxury of leaving work to run to the doctor, health concerns are especially valid.

With commercial space flight becoming a reality, thanks in part to Sir Richard Branson and his Virgin Galactic endeavor, soon the average Joe and Jane will also have the opportunity to experience space travel. Provided they get medical clearance first.

Health Requirements for the Casual Space Traveler

First off, there’s nothing casual about space travel, which is why Virgin Galactic is taking their test flights seriously. Secondly, this transition into casual space travel is resulting in a slew of new considerations.

Acceleration forces, also popularly known as G-forces, are uncomfortable for the healthiest of people. But for those with medical issues, it could result in a lot more than discomfort, which is why questions like the following have to be asked.

  • Can a pacemaker handle space travel?
  • What are the effects of zero-gravity on osteoporosis?
  • How long is too long for certain conditions?
  • Are there male or female-specific conditions to be aware of?

Those conditions run the gamut from high blood pressure and back problems to heart disease and asthma and everything in-between. After all, 264,000 feet above earth is a bad time to discover something was missed.

The problem is in finding a happy medium, according to Marlene Grenon, an assistant professor of vascular and endovascular surgery at UCSF. If only completely healthy people are allowed to fly, Grenon says the number of potential commercial space travelers will decrease substantially.

“We need to address the people with medical conditions who would like to fly,” says Grenon. “If anyone can fly, there will be a lot of conditions that will be different in space, and we need to better understand these disease conditions in microgravity.”

A group from the University of Texas Medical Branch at Galveston recently studied how average people with common health conditions would do in space. They found that, so long as these conditions were well-controlled, they didn’t pose any problems.

It should be noted that the study revolved around simulated flight, not actual flight. You’d have to imagine that stress would be heightened on a real flight, and stress has a way of mucking-up the works, so to speak. Also, you have to wonder how “well-controlled” is being defined.

Though it is interesting, if for no other reason than to contrast the health requirements of commercial travelers with those of astronauts. But as the price tag for commercial space flights is now at a quarter million dollars per person, for most, the question of how healthy is healthy-enough is merely a hypothetical.

Health Requirements for the Professional Space Traveler

Do you remember that scene in the Tom Hanks movie, Castaway, where Hanks uses an ice skate to perform a delicate dental procedure? We’ll bet you his character was wishing he’d seen the dentist before his plane crashed that left him stranded on that island.

Whereas the casual space traveler can get by with certain conditions, the professional space traveler cannot. Everything from STDs to dental health are considered potential problems.

Strong vibrations during flight have been known to shake loose poorly-fit dental fillings. There’s also the matter of atmospheric pressure changes, where gases contract and expand, including the air present in cavities. There’s even a name for it: tooth squeeze. And, of course, you’ll want to know if you have any dental concerns that could result in a dental emergency.

The amount of medical testing that astronauts are required to undergo is substantial to say the least. Everything is in-play, from blood tests and X-rays, to tests involving sight and hearing. There are tests to make sure cardiovascular, digestive, and reproductive functions are operating properly, as well as behavioral and mental exams.

To enter NASA’s candidate program and become an official Astronaut Candidate, you first need to satisfy a few basic qualifications, which are listed below:

  1. BA in engineering, biological science, physical science, computer science, or mathematics. (MAs are preferred.)
  2. Three years relevant experience in one of those areas or 1000 hours as pilot-in-command of a jet aircraft.
  3. Pass the physical exam, including a few specific requirements:
  1. Blood pressure below 140/90 while seated
  2. Correctable vision to 20/20 (LASIK and/or glasses are acceptable.)
  3. Between 62 and 75 inches tall. (Spacesuits are not one-size-fits-all.)

You also need to be a U.S. citizen and endure a week-long process of medical screenings, personal interviews, and orientation programs. And if you’re shortlisted for final consideration, then there is a background investigation.

Though, for astronauts like Cady Coleman, the medical tests are the easy part. It’s the training and everything that follows that can be challenging.

Coleman, a former chemist and U.S. Air Force officer and current NASA astronaut on Space Shuttle Columbia, says being away from family is one of the hardest parts of the job. Well, that and fitting into spacesuits that were built for taller people.

“In terms of the training,” says Coleman, “I would say that the space suit stuff is physically the hardest.” She adds that the mental aspects of the training are just as demanding as the physical. And that being able to work and respond under difficult and stressful situations is an important part of the job.

Even after you successfully complete the Astronaut Candidate program, you could wait years or decades before getting assigned to a crew. During that time you continue to learn new skills, like speaking Russian, and continue to train under difficult circumstances and in mentally-challenging scenarios. But for Coleman, it’s all worth it.

“As a chemist,” says Coleman, “getting paid to fly, to learn survival techniques, having someone describe the space station systems as if you’re going to live there because you are, that’s amazing.”

Casual or Professional?

If you’re interested in becoming a space traveler in 2019, you have just two choices. Pay the price of one ticket, which is currently $250,000. (Though if you’re the type of person who gets motion sickness from riding in a car, going twice the speed of sound may not be for you.) Or make the boldest of commitments and take a run at the Astronaut Candidate program.

As an astronaut, there’s no guarantee you’ll ever make it into space. But unlike being a space tourist, you’re at least guaranteed that if you do, you won’t be sitting next to Clark Griswold and family on their Space Vacation.


Avery Phillips is a freelance human based out of the beautiful Treasure Valley. She loves all things nature, especially humans, and was driven to pursue an Anthropology degree due to her childhood love of Indiana Jones and Laura Croft. Now she lovingly writes about all things great and small.

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