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14 Normal Things Astronauts Can’t Do in Space

In space, astronauts may have more problems than Houston wants to hear about. As for the amount of these problems, the sky's the limit, but for now we'll just stick to 14.

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A tear on eyelashes and cheek.
Afanasiev Andrii/Shutterstock

Astronauts can’t cry

Imagine you’ve been in space for the last 100 earth days and you’re video chatting with your family that you miss dearly—or maybe your wife even had a baby as astronaut Randy Bresnik‘s did while he was orbiting the Earth. If you shed a tear, it won’t roll dramatically down your cheek like it would on Earth. Instead, the tears would form a Jell-o-like blob under your eye because there’s no gravity to pull it down, as explained by astronaut Chris Hadfield.

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shower droplets close up

Astronauts can’t take a steamy shower…

Or shower at all, for that matter. Water is h-e-a-v-y and expensive to lift outside of Earth’s gravitational field, David Donovan, PhD., physics department head and professor at Northern Michigan University tells Reader’s Digest. “Bathing daily is kind of new world thing. In the past people didn’t do that,” Donovan adds. What’s even cooler: the excess water that escapes from hair-washing is turned into drinking water through a water processing system.

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New ceramic toilet bowl near light wall
New Africa/Shutterstock

Astronauts can’t use the bathroom the regular way

Us earthlings take many things for granted, including being able to use the bathroom without floating away. Astronauts have to strap into the toilet to ensure everything ends up in the right place. If not, a hilariously embarrassing scenario unfolds: the corralling of the “brown trout,” Donovan spills. This is when astronauts chase down floating human excrement that missed the toilet.

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sliced rye bread on cutting board close up
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Astronauts can’t consume certain food or drink

In particular, things that are particular. Among bread, these foods are banned in space because they can easily break into small parts and cause harm by getting into machinery or the eyes of a surprised astronaut. In addition, carbonated drinks are limited because of the pressure differences it can cause, Donovan says.

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Glasses of wine and spirits on light background
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Astronauts can’t drink alcohol

Every six days of work in space calls for up to four ounces of sherry, a fortified wine. Or so, that’s what was approved in 1972 for astronauts to enjoy on Skylab missions. This was all fine and dandy until NASA slapped a ban on alcohol due to public outrage over alcohol in space.

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Kid holding pen and writing in notebook. Close up, top view.
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Astronauts can’t write with a regular pen

There’s a gag out there that American’s spent copious amounts of time and effort into creating the illustrious Fisher Space Pen, when the Russians just brought pencils, Donovan says. Nevertheless, the mechanics of the Fisher Space Pen allowed astronauts to write in zero gravity.

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Woman sleeping. Beautiful young smiling woman sleeping in bed
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Astronauts can’t sleep in a bed

Instead of pulling the sheets up before sleep, astronauts strap themselves down for the night. When Donovan saw astronaut Jerry Linenger speak at NMU, Linenger said one of the hardest things to readjust to was the pain of laying in bed, because he hadn’t been used to being pushed into the mattress by gravity.

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Golf ball on tee in front of driver on a gold course

Astronauts can’t hit a golf ball in space

The exception, of course, was astronaut Alan Shepherd; the first American in space, Shepherd was the first to hit golf balls off the moon. “The shot went really long because there’s one-sixth gravity on the moon,” Donovan explains.

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A road sign with arrows pointing in two directions along a quiet country road.
Todd Klassy/Shutterstock

Astronauts can’t take the scenic route

Taking shortcuts is much easier, and more fun, without gravity. On Earth, if you wanted to get to the ceiling in a room, you’d naturally walk over and get a ladder to go up. But space allows you to soar on a diagonal because you’re not restricted, Donovan says.

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blue and yellow trash cans dumpsters

Astronauts can’t waste

Humans have been in space for about 60 years, and we have a nasty habit of leaving things behind, Donovan says. Similar to plastic oceans, space travelers have inadvertently left a trail of debris known as space junk. “This is, unfortunately, a trait of humans. We think it’s a big place but when you look at all these dots [it’s] becoming problematic because you can hit things on the way up or down,” Donovan says.

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side view of muscular african american man doing push ups in gym
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Astronauts can’t maintain muscle mass

Our bodies are used to working against gravity, so in space, astronauts lose bone and muscle mass, Donovan explains, but it’s not catastrophic if they don’t run a few laps. Exercise is built into their everyday routine in order to keep their bodies functioning as they would on Earth.

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Fireman firemen hose putting out fire

Astronauts can’t put out a fire the same way

Linenger was on the Mir space station when a fire sparked. His first reaction was to open a window but that’s certainly not possible in space, Donovan says. Instead, astronauts use fire suppression equipment. Donovan explains that in space, fire burns differently because there’s a lack of oxygen.

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Closeup Portrait of Woman with Freckles and Green Eyes Isolated on a Black Background: Half of Face Visible on Right Side of Frame.

Astronauts can’t have a normal-looking face…

For the first few days in space, at least. Astronauts tend to get puffier faces in the beginning because there’s no gravity to pull fluid down from the face, Donovan recalls from Linenger’s speech. But puffy faces were the least of the worries for these women featured in amazing facts about the women of NASA.

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man sleeping bed eye sleep mask

Astronauts can’t sleep without an eye mask

If you thought sleep for astronauts was complicated enough, factor in a sunrise every 90 minutes. That’s one of the reasons astronauts are issued sleep masks to help them get some shuteye. Now that we’ve cleared up this subject for you, read on to learn about 14 of the most baffling mysteries about space.

Isabelle Tavares
Isabelle Tavares is a journalism graduate student at the Newhouse School of Syracuse University and former ASME intern for RD.com, where she wrote for the knowledge, travel, culture and health sections. Her work has been published in MSN, The Family Handyman, INSIDER, among others. Follow her on Twitter @isabelletava.