It almost never comes up in movies about space unless a character has been taken hostage by an alien parasite, but space travel is incredibly hard on the body.

Radiation, different gravity than bodies evolved for, toxic dust on the surface of Mars or the moon.

Astronauts need to be protected from all of these hazards and treated when they get sick if the safety measures don't work perfectly.

From KERA in Dallas, this is think.

I'm Chris Boyd. Fewer than 700 human bodies have ever been to space, and the majority of them have been male. That's a far smaller sample size

than even a phase three clinical trial for a new medication to be approved in this country.

But given the ongoing interest and investment in colonizing the solar system, a new field

of medicine is emerging to try and make sense of the data.

And if all goes well, my guest has learned that we earthbound people might benefit as well.

Shana Coral is a future perfect fellow at Vox, where you can find her story. Human bodies aren't ready to travel to Mars.

Space medicine can help.

Shana, welcome to think.

Thank you.

So as it stands, if you want to be an astronaut for NASA, you have to be almost preternaturally healthy.

What are some of the conditions that can get people disqualified, even if they are

qualified in every other way? Oh, yeah. So if you, you know, if you have anxiety, if you have asthma,

if you have TMJ disorder, you know, on your jaw clicks. If you use tobacco, that's a problem.

If you have a dependent on acid reflux medications. So almost

nobody we know is going to space is what you're telling us. Yeah, it's a very rarefied select

crowd. And one reason we expect a need astronauts to be in really perfect shape is that space

travel can be really hard on the body. What is it, for example,

about living in zero gravity that can cause or accelerate damage to organ systems and parts of the

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