Going to space might sound like the ultimate once-in-a-lifetime trip for most of us.
But here's the awful truth. Beyond all the excitement - and despite the safety of space stations and spacesuits - some not-so-pleasant and downright weird things happen to your body up there.
Here are some of the extremely strange things that happen to your body in space.
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You get 'baby' feet
It's like going for the world's most expensive pedicure.
The callouses on your feet fall off due to the gravitational changes - leaving you with soft, smooth feet.
Astronaut Scott Kelly shared that he hasn't worn shoes for a year, saying: 'The calluses on your feet in space will eventually fall off. So, the bottoms of your feet become very soft like newborn baby feet.
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Instead, he's swapped his smooth soles for 'rough alligator skin' on the top part of his foot, as he uses this side to get around on foot rails.
Kelly remarked on a Tumblr Q&A saying that it was the "weirdest thing" that had happened to him on the ISS.
You develop astronaut's eye
'Astronaut's eye' is when a person experiences spontaneous bright flashes of light in their eyes. Experts believe this is either due to the result of actual photons being sensed by the retina, or being exposed to cosmic rays.
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The condition - also known as cosmic ray visual phenomena, or light flashes - was found to affect 47 of 59 astronauts in a single 2006 study.
Whilst the science behind the condition is uncertain, the symptoms vary from astronaut to astronaut. Some experience flashes of different colours, others can see shapes like spots or stars.
You have to pee more than usual
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Surprisingly, this is not a result of having to drink more water. In fact, many astronauts have mentioned that during their time in space, they're very rarely thirsty.
The body undergoes a "fluid shift" in space, causing fluids to move around the body. Your body compensates for this by getting rid of what it perceives as excess fluids 'as it would normally.'
Your face gets puffy
With weakened gravity, and thus no force pulling the liquids down in the body, the fluids remain in the upper side of the body. Which is why some astronauts have had the unfortunate experience of these fluids moving to the face.
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And you guessed it, their face goes puffy.
Your fingernails might fall off
Leaving the scariest for last here.
Medically termed as onycholysis, this condition where your fingernails detach from the nail bed and ultimately, fall off.
Hand injuries are the main culprit for this. As NASA explained: 'Injuries to the hands are common among astronauts who train for extravehicular activity (EVA).'
Pressurised gloves can cause restrictive hand movements and create 'pressure points'. Most of the time, this results in pain, muscle fatigue and abrasions, but more severe cases have experienced onycholysis.
According to Dava Newman, a studier of space-related injuries, 'fingernail trauma and other hand injuries are spacewalkers’ biggest complaint.'
It gets worse, so squeamish readers, stop reading here.
Some astronauts would rather get the worst of it out the way than to experience the inevitable discomfort of glove chafing. And by that, I mean they ripped out their own fingernails.
Right, who wants to go to space?!