In the 60 or so years that the job has existed, astronauts have captured the public's imagination. And while many people might think they have some idea of what being an astronaut is like, thanks to the glut of portrayals in movies, real astronauts will tell you that working for NASA is much different from what you see on the screen. In between exciting tasks like spacewalks, they have to worry about less glamorous aspects of the job—like finding lost items that floated away and using the toilet in microgravity.

Mental Floss spoke with two former NASA astronauts about the realities of preparing for and experiencing life in space. Read on to learn about the most annoying parts of the job, the ways they have fun, and their honest opinions about astronaut food.

1. Astronauts come from a range of different fields.

There’s no one direct path to becoming an astronaut. If someone knows they want to be an astronaut from a young age, they need to build credentials in a specific field before they can get the attention of NASA. "They're looking for people who are qualified, meaning that they're high-achieving military people or people from civilian life, generally with an advanced degree," Mike Massimino, a former NASA astronaut and professor of mechanical engineering at Columbia University, tells Mental Floss.

To be considered for NASA’s astronaut program, candidates must have U.S. citizenship, hold a master's degree in a STEM field, and have at least two years of related post-grad professional experience or at least 1000 hours of pilot-in-command time on jet aircraft. Two years toward a doctoral program in STEM, a completed doctor of medicine or doctor of osteopathic medicine degree, or completion of a nationally recognized test pilot school program are also accepted in place of a master's degree. Because space flight crews require diverse skill sets, the criteria doesn’t get more specific than that.

"I was a Ph.D. research engineer professor when I was picked," Massimino says. "I've flown in space with engineers, with test pilots, helicopter pilots for the military. I've also flown in space with a geologist, I've flown in space with an oceanographer, and I've flown in space with a veterinarian. So it's really varied. There's not just one route."

2. Astronaut training involves everything from class work to military survival exercises.

NASA astronaut Garrett Reisman on a spacewalk in May 2010. NASA's Marshall Space Flight Center, Flickr // CC BY-NC 2.0

Candidates accepted into the astronaut program must complete years of training before they're ready for spaceflight. A lot of that training takes place in the classroom and involves learning about different space vehicles and systems. Astronauts also undergo physical training in the real world. According to Garrett Reisman, former NASA astronaut and the director of space operations at SpaceX's headquarters in Hawthorne, California, one of the most intense courses has nothing to do with preparing for life in space.

"We do the same SERE [survive, evade, resist, escape] training that military aviators go through," he tells Mental Floss. "The idea is that if you fell out of an aircraft over enemy terrain, you got to know how to survive without help. You have to learn to live off the land, what plants you can eat, how to make a shelter and all those things."

The T-38 jets astronauts fly as part of their training have ejectable seats, so landing somewhere unfamiliar is a possibility. But astronauts only fly over the continental U.S., so they likely won't ever need to use the full extent of their SERE training. "What are the odds that you parachute down and there’s not a Starbucks right there?" Reisman jokes. "All you need to do is give me a Starbucks gift card and I’ll be fine."

3. Exercise is a vital part of the job.

Exercising is more than a way to pass time in space: It’s essential to an astronaut’s health. The human body isn’t used to moving around without the force of gravity, and for this reason, all astronauts must make resistance exercises part of their daily routine.

"You do have to spend two hours every day exercising," Reisman says. "If you're up there for a long period of time, you can lose a lot of your bone and your muscle mass if you do nothing, so the way we get around that is by doing intense resistance exercise."

Astronauts can lose up to 20 percent of their muscle mass on an 11-day space flight due to the lack of gravity [PDF]. But zero gravity also makes free weights useless, so instead, astronauts maintain their strength by using a device outfitted with two small canisters that create a vacuum they can pull against with a long bar. A bike and treadmill (with a harness) are also available on the International Space Station. Strength is required to perform certain emergency procedures when the ship re-enters Earth's gravitational field, so staying fit in space is vital.

4. Astronauts do most of their work on Earth.

Astronaut Mike Massimino practices repairing a portion of the Hubble Space Telescope while training at NASA's Johnson Space Center in Houston, Texas. NASA Hubble Space Telescope, Flickr // CC BY 2.0

In order to become one of the few people to travel to space, astronauts must be willing to do a lot of work at home. "A NASA astronaut’s job is mainly spending your time on Earth," Massimino says. "You're going to spend the vast majority of your time on the ground, either training or working on technical issues or helping other people fly." Throughout his nearly two decades with NASA, Massimino spent less than a month total in space. Reisman was with NASA for 12 years and spent a cumulative 107 days of his career in space.

5. Astronauts don't make as much money as you think.

One of the biggest misconceptions astronauts hear about their work relates to their salary. While they are paid decently, astronauts don’t collect the massive paychecks some people might assume comes with such a high-profile job. "We don't make a heck of a lot of money," Massimino says. "We make a standard government salary."

Astronauts are paid according to the federal government's General Schedule pay scale. Most federal jobs are assigned a General Schedule (GS) grade that determines their starting salary, and the pay increases as they gain experience. Astronauts either qualify for grades GS 13 or 14 (the highest grade is GS 15) and make between $104,898 and $161,141 per year. For comparison, Fish and Wildlife administrators are paid similarly at the right experience level.

6. Astronauts lose things (but not for long).

Even in a place as tight as a space station, astronauts still manage to misplace their belongings. Thanks to the lack of gravity, anything they let go of immediately drifts away, which can cause problems when they’re not paying attention. Massimino recalls one incident that happened to his crewmate Mike Good: "He had his grandfather’s watch with him, and he comes up to me and goes, 'Mass, I can’t find the watch.' We’re looking all over the place and I stop after a minute and go, 'Mike, it’s inside here somewhere.'"

They eventually found it trapped inside the airlock. The air filter is another common place where lost items end up: Without gravity interfering, the air flow will carry any floating objects there. "One thing we would say is, 'If you can’t find something, just wait,'" Massimino says. "You'd wake up in the morning and look at the filter and see like aspirin and a piece of Velcro or something, because everything eventually would get there."

7. Astronaut opinions on the food in space are mixed.

Despite its reputation, space food has some fans in the astronaut community. "Astronaut food is great," Massimino says. "We had ravioli, lasagna, shrimp cocktail, fajitas. It was fantastic."

Reisman holds a much different opinion of the meals he ate in space. "It’s terrible. You don’t go to the space station for the food," he says. While he didn’t love the American and Russian provisions that made up most of his diet in space, he did have nice things to say about food from other agencies. "The Japanese and the Europeans, when their astronauts would fly, they had special food that was provided by their space agencies. The Japanese sent up yakitori and miso soup and that was delicious. And the Europeans had pâté. That was much better."

8. Astronauts find time to have fun.

NASA astronaut Mike Massimino smiles during some extravehicular activity (EVA). NASA Hubble Space Telescope, Flickr // CC BY 2.0

Between work, meals, and exercise, astronauts don’t have a ton of free time in space. Duties like maintenance, installing equipment, and conducting experiments take up the majority of their day. Sneaking in recreation usually means staying up past their scheduled bedtime, which Reisman confirms most astronauts do. One of his favorite activities to do aboard the International Space Station was taking pictures of Earth. "You could take photographs of places on Earth that are special to you. I got a picture of my hometown, which is pretty cool. As far as I know, no human ever photographed that particular town from space before."

9. Astronauts think movies set unrealistic standards.

The science isn’t the only thing that’s unrealistic about Hollywood’s portrayal of space travel. "I think the biggest misconception is that we're all tall and good-looking," Reisman says. When working as a technical advisor for 2019's Ad Astra, he jokingly brought up this gripe with the movie’s star Brad Pitt. "I said, 'I’m kind of pissed off at you. Think about who they cast to be astronauts in all these movies and TV shows. Matt Damon, Matthew McConaughey, George Clooney, Brad Pitt. People meet me and they’re disappointed.'"

Reisman doesn't hold this against the actors, however. Pitt reminded him that the stars portraying astronauts on screen have plenty to be envious of themselves. "Brad said: 'Well, Garrett, I can't actually fly a spaceship. The only talent I have is being able to stand in a certain spot and read something that someone else wrote. I got nothing else.'"

10. Going to the bathroom in space is an ordeal.

If you’ve ever wondered how astronauts poop in space, the answer is: with great difficulty. "Taking a dump was not easy," Reisman confirms. Without the help of gravity, using a toilet in space becomes a complicated operation. Astronauts must strap their feet down to keep from floating away and create a perfect seal between the toilet seat and their butt cheeks. The toilet itself uses a vacuum hose to suction up the waste. The process is so complex that using a space toilet is part of an astronaut’s training. It's not unusual for a bathroom break that normally takes a few minutes on Earth to last half an hour in space.

11. In such a competitive field, astronauts need to be persistent.

NASA's astronaut training program is extremely competitive. The agency selected just 12 people out of a pool of 18,353 candidates in 2017, which comes out to an acceptance rate of 0.065 percent. Massimino had to apply four times before he made it into the program.

"I was rejected outright twice while I was in grad school. The third time I got an interview and failed the eye exam, so was medically disqualified." NASA considers candidates with less than 20/20 vision today as long as it's correctable, but that wasn't the case when Massimino was applying. "I went through some vision training with an optometrist, and I was able to teach my eyes to see a little better. I was able to apply a fourth time, and I was picked on my fourth try."

According to Massimino, that level of commitment to his goal ended up being relevant to the job itself. "The job is a lot of late-night simulations, you have to pass exams, you have to work with your teammates. And unless you have a real interest in it, it's going to be tough."