We Don’t Know Why Space is Bad for Our Eyes

Since the 1980s, NASA scientists have known that space travel can negatively impact your vision, but they're still unsure exactly what causes it. Symptoms of SANS (spaceflight-associated neuro-ocular syndrome) can worsen over time, so if we're going to start shipping humans to Mars, we've got to figure out how to prevent or mitigate the symptoms.
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[@Rajclaw]

Doctor: “I’m sorry, you have sans” Astronaut: 💀

[@ok-tr1nw]

Maybe its the way your dressed

[@alicearaujo2030]

that astronaut's having a bad time

[@AchievementDenied]

Some say doc is the Comic of these parts, but others say he's a Serif. Still collecting data, but that's a Mettaton of information to sift through

[@duskadown6751]

these puns are an eyesore

[@GoldenAdrien]

HAHA

[@nopperabooo7470]

One of the long term effects of solitary confinement is vision loss. Because the room is so small, your eyes don't need to adjust to see things that are far away, and you gradually lose that ability. I wouldn't be surprised if someone who spent a long time in a space station also experienced this

[@pauldeddens5349]

Thats what I was thinking. Too little eye movements and refocuses leading to an extremely long term eye fatigue. It makes me wonder if the eye adjusts looking _out_ towards space though. Since everythings so far away, does it treat it all as a single plane?

[@RealDealy]

That and the lack of sunlight which forces bloodflow to the eyes from the infrared spectrum, and dopamine release from the blue light spectrum But, in this case for space astronauts I think it's just the lack of gravity that causes the nerves to lack proper blood flow to the needed areas. It's easy to fix. My comment in the comment section explains it. I wish I could link it cause i don't want to type of all of that again

[@odette5031]

Can you regain that vision loss?

[@RealDealy]

@@odette5031 idk

[@Biosquid239]

Many people here confident that they know whats happening. If it really was that simple this wouldnt be an issue thats been going on for 40 years...

[@Snow_Sailor]

I mean it only makes sense that when you're outside of our natural gravity some of our body is *_gonna have a bad time_*

[@TechySeven]

Yup. Although maybe one day, probably in a million years or more, we'll hopefully have naturally evolved and adapted to Zero-G Environments.

[@RightTesticle]

​@@TechySeven I'm sure we'd have found another solution within a million years rather than just naturally evolving.

[@TechySeven]

@@RightTesticle Most likely, yeah. IF we can even make it that long.

[@EnderSpy007]

"I understood that reference!" Undertale will plague my mind until the day I die. Curse you hyperfixating teenage brain!

[@justinbarter1546]

Your also getting much more radiation and different particles hitting you that our atmosphere blocks mostly out.

[@victoriarees4540]

My eyesight is so bad I'm convinced I've already been sent to space

[@militantpacifist4087]

It was those aliens that keep appearing.

[@keiz5052]

your could say that trying to see is.. a bad time

[@mrnice4434]

F'ing aliens

[@loyalfish2761]

Did it hurt when you fell from heaven?

[@Rorschach1024]

​@@loyalfish2761 no, but that sudden stop did...for a fraction of a second.

[@seratheeducatedfeline4227]

There’s another important reason to understand SANS: for the sci-fi writers to go nuts using it as a plot point.

[@ginnyjollykidd]

YES! SF writer, here!

[@Skeazix]

I was totally thinking this.

[@kaushalsuvarna5156]

Was already thinking of it

[@josephkoester3217]

If it was humorous sci-fi would it be comic sans?

[@kaushalsuvarna5156]

An astronaut goes blind, but he finds faith and his pineal gland awakens He then sees the Matrix in gold

[@VaradMahashabde]

"Right now NASA considers SANS the top space flight risk" Papyrus, come get your brother back already!

[@sylvercritter]

have you considered why sans is such a problem? nasa killed them. they killed them all.

[@goofballbiscuits3647]

Honestly, Sans is the least of their problems... Flowey is the worst nightmare.

[@hotstreak164]

My dad was an airline pilot and flew planes for over 30 years. Late in his career got folds in his retina which ruined his 20 15 vision (better than what is considered perfect) Could that have been SANS? He never went to space, but it was very strange and the eye doctor he saw didn't have an explanation

[@CarrieMHB222]

Hmm. Wondering then if it’s the pressure and jostling of taking off? An astronaut would have much more pressure and jostling with one rocket launch while an airline pilot would acquire the effects over a longer period of time.

[@TragoudistrosMPH]

Was that also before the uv blocking glass was added for pilot safety?

[@austinfaust3374]

That could have been plain ol' macular degeneration

[@DrVictorVasconcelos]

@@CarrieMHB222 These pressure stresses that are very short are not really likely to cause anything chronic, except as a chronification of an acute problem. It's really the low gravity for extended periods that should change the size and format of your eyes, which is the primary reason people's eyesight gets worse between puberty and adulthood--unfortunately, eye development is not a conformal transfomation . But one possible reason is cosmic rays.

[@DrVictorVasconcelos]

@@austinfaust3374 Which is specially likely to happen if you're spending so much time high enough that cosmic rays are significantly more likely to hit your eyes.

[@DoctorEyeHealth]

Love the fact you showed things like the choroidal folds. The one thing I would add is what happens when cerebral spinal fluid pushes on the optic nerve. It essentially pinches the nerve and stops the retroaxoplasmic flow within the nerves, this causes optic nerve edema and can lead to permanent nerve damage and even fluid leakage inside the eye in some cases. Love the video and all that you do 🖖

[@WestCoastWheelman]

Channel name checks out. Pin this comment on top!

[@militantpacifist4087]

I never thought Undertale was going to get involved in astronauts’ health.

[@oracleofdelphi4533]

Why is it that all the fun stuff makes you go blind?

[@pokerraper1]

@@oracleofdelphi4533 because it leads to a bad time

[@avawalker2746]

0

[@gamingcookiereal]

toby fox really is everywhere

[@Always_LaggginTTV]

Reading this comment before watching the video and I’m very confused Edit: ah, I now see

[@atigerclaw]

Man, I knew that Genocide Run on Undertale would come back to haunt me. But I didn't think it would be like this...

[@DarkSnideoftheRainbow]

Are you telling me we're giving our astronauts SANS eyes?

[@arthurboothby4847]

Sans teeth, sans eyes, sans taste, sans everything.

[@ok-tr1nw]

@@arthurboothby4847 *MeGaLoVania intensifies*

[@Gerben0]

👁👄🧿

[@Zappygunshot]

I do love the idea of space truckers that spend a lot of time in microgravity being identifiable by their swim goggles. Just a cool little character design thingy for sci-fi stories.

[@porcelainboy264]

That would be awesome

[@ashleeminnow8453]

"We believe education is a human right." SEE, now this is why I watch this channel and it's sister channels and why I love it so much. I am absolutely fascinated by every video and what I learn from it and the compassion shown thru it is marvelous. Thank you guys for being you!!

[@isaacm1929]

Studies in Space Medicine fills all humanity with DETERMINATION.

[@Camaika1997]

I hope you have a great day!

[@isaacm1929]

@@Camaika1997 And for you a great week!

[@finlay9616]

Disagree

[@isaacm1929]

@@finlay9616 Great, that's how science works!

[@squidward5110]

Does it? I have a solution: stop sending people to space it's pointless

[@harry3life]

Honestly it's already amazing that the human body doesn't just completely stop working in zero G. Literally millions of years of evolution under gravity, and there is not one critical function in the human body that can't work without it. That's insane.

[@DKFX1]

Yes, but at the same time zero g is just the state of appearing weightless, a very similar affect to the body happens simply by moving in water which our body unsurprisingly is very adapted to.

[@maalikserebryakov]

Haha you believe in tbr Fairy tale of Evolution . God created YOU and ALL thing

[@johndetheshape3095]

@@maalikserebryakov are you one of those types of people who Think dinosaurs and fossils are a conspiracy and not real?

[@Tatusiek_1]

@@DKFX1 not really because all of your insides are still being pulled down by earth’s gravity while in water.

[@DKFX1]

@@Tatusiek_1 But there an approximately equal buoyancy force pushing you up, so your appear weightless. This is why astronauts often train in underwater chambers.

[@alexsalcido2694]

Couldn’t it just be the lack of gravity? I imagine our bodies which have adapted for gravity over years and years would encounter some problems spending long enough in 0 g. Also explains why they return to normal when they come back

[@shigekax]

It is, but they're trying to figure something more specific, because then it could be possible to counter it.

[@alexsalcido2694]

@@shigekax I wonder if calf and fore arm exercises could help distribute fluid and blood flow more evenly similar to fighter pilots trying to keep blood in their heads under intensified gravity but reversed.

[@infiniteplanes5775]

I think it has to do with that as well, especially since it was mentioned that brain moves higher

[@Mulberrysmile]

Seems pretty clear that gravity is involved. They need a centrifugal substation to test human health and plant growth. I’m sure it is a matter of $…least expensive treatment versus providing more earth like habitat.

[@ShooprDoopr]

@@alexsalcido2694 That's not a bad hypothesis. The astronauts do have pretty strict exercise regimens that they follow while on ISS (look up videos of the treadmill or ARED). There is a lower-body negative pressure (LBNP) device that the crew like to use when they have time that does a pretty good job of coaxing more fluid back into the legs (simulating the effect of gravity on Earth). I've heard this- haven't officially read it- but the LBNP supposedly does a good job at relieving headaches associated with the fluid shifts experienced in space.

[@op4000exe]

We really need a spin "gravity" experiment in space to see if these issues are essentially just caused by the lack of gravity. Something with a long enough tether to avoid the coriolis effect causing nausea.

[@AsheeBree]

Thank you Hank for making my tuesday less gray with the word "SPACE! eyes" 😄

[@itsonlyafleshwound9024]

Man, i really wouldnt have thought that my eyes were gonna have a bad time, in space.

[@militantpacifist4087]

They already do with sun rays.

[@pokerraper1]

My eyesight is already a joke

[@okman9684]

Like you are going to space in your life

[@canwenot573]

Am I the first one to reply who gets this joke..?

[@rehiletemecanico249]

Hehehehehe

[@redims8967]

Sans Eyes sounds like something you’d say at a French restaurant.

[@GenRN]

I like my fish sans eyes.

[@militantpacifist4087]

“Can I please get the Chicken a la Sans?”

[@MontgomeryWenis]

Whoa. It's almost like _sans_ is an actual French word. Crazy. 🤦‍♂️

[@cfltheman]

@@MontgomeryWenis Sin in Spanish.

[@Wolfie54545]

@@MontgomeryWenis that’s the joke. Unless IM getting wooshed here.

[@Krabby7Playz]

Who knew space would really dunk on the eyes

[@SilentRacer911]

I could’ve sworn that we already figured it out between the extra UV, microgravity, weird atmosphere (not including all trace elements) and the decrease in pressure all add up. It wouldn’t surprise me if there was a genetic component as well

[@mkseed9188]

Sources?

[@SilentRacer911]

@@mkseed9188 why source known biological facts? It’s already proven that UV radiation would damage the eye along with microgravity’s effects on an organ that’s designed for Earths gravity. The ONLY speculation which I would think would have some unknown effect is missing all the trace elements from our atmosphere. Our bodies evolved over hundreds of thousands of years if not millions on the earths atmosphere with many other trace elements. Have we really studied what they do when inhaled? We only started having these strange careers in the last 80 years where people are outside the atmosphere for longer periods like a saturation diver or astronaut.

[@WV-HillBilly]

it just makes for a much more delicious clickbaity video to be like: *SCIENTISTS ARE BAFFLED BY THIS* in reality, scientists very rarely state anything as fact and acknowledge there's always more to be learned - it's not untruthful to say "it's not fully understood" (even though it's like 99% understood)

[@sid6645]

I think its more like finding ways to counteract the issue.

[@NachoDaMan]

Source: trust me bro

[@zibbitybibbitybop]

*plays Megalovania on loop in honor of SANS becoming an official medical diagnosis*

[@prim16]

In honor of SANS, we should fill the entire comments section with terrible skeleton puns.

[@Eyerleth]

You feel like you're going to have a bad time.

[@zcarp8642]

I'm sure they'll be humerous

[@danm8004]

​@@zcarp8642that one tickled my funny bone.

[@Eyerleth]

@@zcarp8642 Tibia honest, I saw that one coming. No fibula.

[@orsonzedd]

​@@Eyerleth vertibruh

[@OceanMcIntyre]

It also happens less often in women than in men. Some of us experience this same thing here on Earth (called idiopathic intracranial hypertension (IIH) or pseudo tumor cerebrii (PTC)).

[@Samirustem]

If it's presure issue maybe also size related. I wonder if that sex dependence was controlled by size

[@puddlejumper3259]

Except for the part where he specifically cites that not everyone who has SANS has this increased pressure and most who have the increased pressure do not have SANS.

[@OceanMcIntyre]

@Samir Rustem they've looked at sex and the difference is still there. It happens less in female astronauts. It's more likely a physiologic difference between male and female anatomy that has yet to be fully understood. Veins, which is how blood flows out of the system and back to the heart, normally has small valves to prevent back flow, whereas arteries have thin walls of muscle fibers. It's possible that the lack of 1G gravity has a negative influence on either the arterial muscle fibers, or that the veins can't manage flow without the pull of gravity. Estrogen and progesterone levels may also have an influence in how bodies manage blood and CSF flow since only female bodies are made to manage more than one circulatory system at a time (fetal systems are also weird in this way).

[@moroteseoinage]

Positive Train Control?

[@Dirk_Mcgurk]

lack of gravity creates a ton of problems. what about an hour of centrifugal movement where the point of rotation is by the shoulders. it doesn't have to be fast at all. enough to send pressure away from the head and shoulders almost like gravity. 2 or 3 rotations a minute. eye masks used. would they get dizzy? would it do anything?

[@LFTRnow]

This makes me wonder about the more ordinary conditions to check. Are the eyes in space subjected to particularly low pressure for a long time (similar to an airline flight), or perhaps there is too much or too little humidity for a long time? I'm reminded of when one spends too long in a bath or pool and get wrinkled fingers, or a dry throat after a long flight.

[@clickbaitcancer120]

Sounds more like the opposite, they're subjected to particularly high pressure, since gravity would normally pull blood into our legs, which we have developed to withstand, meaning that in space more blood will be pushed into our upper body and head.

[@crow9659]

don't say it don't say it don't say it don't say it don't say it

[@militantpacifist4087]

You like Undertale and Deltarune don’t you Squidward?

[@EnderSpy007]

If I saw this video years ago I would have freaked out knowing that Sans is an actual medical condition. I was so obsessed with Undertale back in the day

[@gradeabrandon186]

Astronaut: “Why do I hear boss music?”

[@militantpacifist4087]

Doctor: Unfortunately you have Sans.

[@sarahblack9333]

​@@militantpacifist4087 you're gonna have a bad time

[@Envy_May]

DUDUDUT DUT, DUT DUT DUUUU DUDUDU

[@sib113]

You might say, the Astronauts are having a "bad time"

[@hazmatt8349]

Can we call our normal Earth vision Serif?

[@GenRN]

Good one. 😂

[@sinatrabone]

Credit to Hank: the entire video is a set up for the Sans pun. Which was a slam dunk. Also credit for the assist to whichever scientist coined the acronym.

[@neptune612]

Be honest... This whole episode was based around that sans-vision problems joke!!🤣

[@Envy_May]

puns, huh......perfectly in character.....

[@MontgomeryWenis]

My first thought was ocular atrophy. Is it so hard to believe our eye muscles lose strength with less to actually focus on? I mean, space is pretty empty and dark.

[@leg-1-ace713]

Unlikely as just looking at a paper in your hand or writing on a screen will use those muscles.

[@MontgomeryWenis]

@@leg-1-ace713 Just a hypothesis. 🤷🏼‍♂️ I'm not familiar with the average day of someone floating in a spacecraft.

[@leg-1-ace713]

@@MontgomeryWenis I'm an optometrist, and while I do not know for sure atrophy won't occur, it is less likely as all the muscles in the eye are used everyday by people on earth and in space

[@RealDealy]

@@leg-1-ace713 But, they need to get blood to flow there for them to work efficiently. With no gravity you are forced to make your system work. Read my post in the comment section, I don't feel like typing all of that again

[@xero6774]

​@RealDeal I don't think gravity really affects blood flow? we push blood around regardless, it's not like it'll require more force or anything

[@eyevou]

Not using Megolavania as an Outro was a big missed opportunity.

[@1jotun136]

Y'all have fun. I'm waiting for grav plating and deflector shields.

[@davidbetancourt4028]

Wouldn't you just need a couple of rotating habitats around the central axis of the ship? Centrifugal force at that scale wouldn't be perfect, but having 0.25 Gs of force might severely attenuatethose problems.

[@infiniteplanes5775]

Why?

[@ockertoustesizem1234]

that's not easy to build

[@davidbetancourt4028]

@@infiniteplanes5775 Remember seeing the movie The Martian? They had a rotating habitat on their ship. Think of the carnival ride called The Gravitron, where it spins you around where & your back is stuck against the wall. It's like that but in space. Since it's constantly spinning along the axis of propulsion / movement, you can simulate gravity this way. I only suggested enough spinning to simulate 0.25 Gs. If I did the math right, that'd be about 5.4 rotations per minute for a 50 foot wide circular structure, which would be spinning at a rotational velocity of about 4.32 meters per second _(9.66 miles per hour)._

[@davidbetancourt4028]

@@ockertoustesizem1234 Anything and everything for space is hard to build. I would assume you don't know the added degree of difficulty this would bring to the project or you'd likely have estimated. If the space eyes thing becomes a confounding variable, I'd imagine this is the way to go. The only real problem, beyond the additional engineering effort would be perhaps the requirement of expending fuel to stabilize periodically. That might make it a non starter, or perhaps there's a way to do this with moving weights that shift on axis depending on the rotation speed changes _(because it'd change when people leave the habitat)._ I dunno.

[@Brian-dv3xd]

Been watching you for 10+ years...to another 10! Thank you

[@juangil384]

I feel this guy does a great job getting the idea between brains... Even his nerdy humour is excellent

[@bskosko8780]

My first thought was the increased pressure. Being in an enclosed area. Maybe light has something to do with the folds. Since are reflect it. Very interesting video.

[@stevensmutko1408]

I'm going to comment on this even though I know nothing about the eyes, its possible that the issue is with the Vitreous humor because of the zero g effects it could cause it to become unstable and create low and high pressure zones causing retinal folds and also could cause it to be easier for crystals to form in the liquid due to not needing to have as stable nucleation points. Not a medical person here but maybe we should look into that first. Good luck researchers hope this helps.

[@xxportalxx.]

I wonder if cosmic rays play a part in it, I remember the Apolo astronauts reported seeing shooting star like streaks in their vision from the radiation hitting their retinas.

[@lukaylitapio8684]

Not Sans taking my fricking eyes

[@CarlosSpicyWang]

Can't get sans if you don't have eyes.

[@combuster12]

Reddit downvote

[@lowearthsurfer]

​@@combuster12Banned by Subreddit moderator

[@wow-roblox8370]

*megalovania intensifies*

[@bhami]

We badly need a spinning space station where we can do long-term low-gravity experiments. Maybe something like Martian gravity (~1/3 G) is all we would need to prevent SANS.

[@seok-posuh6898]

I've got a theory. Microgravity/zero gravity. It has been proven that greatly reduced gravity is bad for human muscular-skeletal structure. So therefore, microgravity is going to hurt eyes which is made of muscular tissues with alot of fine vessels/capillaries. Plus there's increased exposure to radiation/magnetic fields and god knows whatelse, as spacecraft shieldings and spacecraft visors aren't nearly good as Earth's atmosphere in filtering out harmful radiations. But what the hell would I know. P.S. treatments could include swim goggles that induces minor overpressure around eyes without popping any capillaries? Just to stimulate and increase blood flow around the area so it's more closer to Earth conditions? Include better filters from harmful space radiations too.

[@issacpalmer4715]

Consider the following, have a room rotating around the middle of whatever ship you're on to add some G's pulling the fluid away from the head. Like a relatively slow centrifuge

[@Voidwalker093]

Touching on health here is great, we often consider going, but most won't be able to due to health. Imagine a severe diabetic in space.. Where is the insulin supply ect. There is a lot medically to figure out, not just the vessel!

[@fariesz6786]

_•cries in type 1•_

[@Croz89]

At this point it's easier to just screen out people with those conditions, since it's not common enough to be a problem. It's something to think about for the future though.

[@ockertoustesizem1234]

if you're diabetic then the solution is simple, don't go to space

[@charlesventer]

Thanks Hank & team!

[@angelao1723]

Everytime you mentioned their retinas could fold while in space I felt my eyelids tighten like I was going to be able to keep my own retinas flat by tightly squinting… 😂

[@kyriejones6060]

I think we should look for similar vision problems in people who also spend a lot of time in extreme environments. Deep sea divers, pilots/flight attendants, people who climb Mount Everest, people who operate zero gravity experiences, and people who spend a LOT of time in confined quarters among others may also experience signs of SANS which may help scientists pinpoint what causes the issue.

[@Ryukachoo]

The awkward phase when we have money for deep space missions, but not enough to make a proper centrifugal habitat, so we have to engineer solutions strange gravity issues instead of just making gravity

[@maskedmarvyl4774]

I've been suffering from space eyes my entire life, and I've never been in space. I feel cheated. "In space, nobody can hear you scream.....or see you scream....because it's space".

[@gradeabrandon186]

Imagine hearing Megalovania suddenly while drifting through the emptiness of space

[@Brown95P]

@0:23 "I just like to call it Space Eyes" I like to call it Funny Undertale Joke myself. Also thanks for killing any ambitions I ever had of wanting to be an astronaut with all those spinal taps.

[@brukujinbrokujin7802]

To any scientist out there trying to figure out sans. I have story that might be of use. I have 14 dioptri myopia, its bad. But whenever i go to gym, my eyesight went significantly better for a few hours after gym. But the next day it gets to bad again. My hypothesis, when i exercise, there is bodily function that correlated with muscle, and it also helps muscle that controls lens in the eyes. Therefore, making the eyes more stronger and the lens thinning more accurately. After seeing this video, might suggest to look on the correlation between lack of exercise and bad eyesight. The astronaut might get "Bad lense muscle" because they dont use muscle often as in earth, like me

[@Croz89]

Sounds like something a PhD student might be interested in.

[@LirioFloyd]

I have been experiencing something similar with my vision. Except it’s not exercise causing the improvement. It’s staying off my phone. My symptoms specifically are binocular double vision and very poor night vision. If I stay on my phone for too long the double vision comes back, but if I remember to take breaks then I don’t have that problem and my vision at night is a lot better. It’s as if my eyes stay “stuck” focusing at the distance that I use when I’m looking at my phone so when I try to see far away my eyes are misaligned.

[@tehKap0w]

i can't believe his pun wasn't _"going to space sans SANS!"_

[@Bitchslapper316]

I wonder if increased exposure to cosmic rays plays a part. I've heard astronauts talk about seeing flashes if light even when their eyes are closed and they explained it as a cosmic ray.

[@ares106]

They seem to think it’s microgravity but it could be the constant bombardment with cosmic rays not filtered out by the atmosphere, sort of like snow blindness.

[@adaroben1104]

Ships suits and stations are designed to shield from that, and if you were getting cosmic ray’d there are way bigger problems than just your eyes. I don’t know how it would cause physical deformations of tissue.

[@Cr3zant]

That doesn't make sense, no astronaut since the late 80s has exited earth's atmosphere. No astronaut in the modern day has ever entered space and only goes as far up as the ISS, which is a mere 400 km up, not even halfway through the extent of earth's atmosphere.

[@gerrimilner9448]

reserch into vision may help lots of people. possibly finding treatments that would work for hank or myself even

[@mesmoe-rizing]

I hope they really make a break through. I have Idiopathic Intracranial Hypertension, my cousin had it before he passed away from covid. If they can find out how CF flow functions it will make life so much easier!

[@TrashEater2729]

"Where are we?" "We're in Undertale"

[@ecurps1]

Is there a side-effect of uncontrollable punning? X3

[@fafflerproductions]

I genuinely didn't know Hank did things outside his channel. Looks like I have a LOT more of his content to watch!

[@jameshill2450]

... "if it's a round trip"? If it's not, then it would be a lot longer than 2 years.

[@budd2nd]

All of the SANS symptoms sound like they are caused, by a lack of gravity. Which makes sense, as our bodies evolved with gravity. So how are the artificial gravity simulators coming along?

[@TheStaggpaul]

I am wondering if the cultures who grow up around water and swim a lot have some kind of condition like this? Also, really need to invest in technology for “artificial gravity”.

[@robinf6314]

The German DLR (German space and aeronautics research Center) conducts Tests on this in another way similar to the water bed. Volunteers lay in a bed for weeks with their Heads tilted down a bit, which causes things in your head to shift up similar to 0 Gravity.

[@feedbackzaloop]

As if there is anything that isn't bad for the eyes...

[@berttorpson2592]

Swim goggles on all astronauts would be hilarious

[@THINKMACHINE]

I wonder if sleeping in a rotating drum or pod to simulate gravity would solve the problem, seeing how well it responds to simply coming home and the cumulative nature of it. Normally this method of producing gravity-like force is problematic as you end up with serious issues with balance and motion sickness unless you build the entire thing large enough, though for someone laying (relatively speaking) down and resting the size requirement is probably far smaller, especially if the drum/pod is opaque and the occupant's senses can be easily convinced that they are in fact simply in regular gravity. It'd probably do a lot for the comfort of the astronauts too.

[@gfdgfdgfff]

You feel like your eyes are going to have a bad time.

[@blastlightstar]

i don't know how to even begin on how HILARIOUS it is that the SANS acronym is _space-related_

[@fuzzy-one-z7205]

Could it be the pressure change like cataracts

[@Roope00]

I'd wager it's to do with the low gravity, as there is essentially nothing pulling down on those bodily fluids which then build up pressure in the head. I thought maybe simulated gravity would be a solution, but considering it wasn't even mentioned, it was probably written off in the beginning already due to some good reason.

[@OceanMcIntyre]

Cataracts isn't from pressure. I think you're thinking of glaucoma.

[@RolandoGarza]

I didn't see that SANS pun coming.

[@nBasedAce]

I think that what is affecting us is the lack of gravity, the real question is how it is affecting us.

[@ineffablemars]

yep. It also affects every other part of the body. I think artificial gravity is something they need to work on if they want more travel into space.

[@catatonicbug7522]

Makes perfect sense. The human body is 75% water, and evolved to handle earth gravity while standing upright. I imagine hanging a person upside down would lead to similar side effects.

[@ThatTravGuy]

That name is gonna give me a bad time.

[@michaelborror4399]

Going to the moon sounds like there's alot less to worry about than mars without relying on cave lion/snakes like osiris for everything at least. With maybe even a few mushrooms greenhouses on the dark side of the moon, with no wind or atmosphere? And futuristic interior heads up displays, with outer lens cameras, and a slideable metal outer face visor maybe, and naturally a dubayen landing site, and wilderness equipment center, maybe one day.

[@Justagamerl]

Eyesight is one of the flimsiest systems in the human body. It starts to temporarily degrade after 18 hours without sleep. Blurry vision is one of the earliest warning signs of diabetes. It becomes permanently damaged by staring at a book or television screen for 2 hours a day.

[@anieldayyanelday1771]

3:28 aw, how nice of those people to donate their eyeballs

[@gorgonzolastan]

Capital One shopping 🤮 Must be tough times at Sci Show

[@tylergully7389]

i feel like almost all of this is probably just due to changes in blood flow, as changes in gravity can change and sometimes even reverse blood flow in certain areas like your jugular

[@theFminusclub]

Uh first?

[@hassassinator8858]

congratas

[@Andytlp]

So this just might be the biggest hurdle to overcome. It's not even about just getting there.

[@yohaan9]

This was interesting and VERY informative!

[@sc3ku]

5:37 that suit is like the opposite of compression socks

[@Voldycat]

Wasn’t expecting all these undertale references in the year of our lord 2023 but I am very pleased.

[@shepardice3775]

This is why I think any travel to deep space without a way of simulating gravity is absolutely crazy. Sending astronauts all the way to Mars in a capsule is nuts. Could you imagine spending 2 whole years in something the size of a large van with no ability to go outside? With other people??

[@GreenPiCat]

2:40 was not prepared how creepy this MRI w the changing depth would look 😱

[@NexuJin]

To quote a Dr. Weir: "Where We're Going You Wont Need Eyes To See"

[@phrozenwun]

ISS 2.0 needs a centrifuge based living/exercise ring. We need real data on the detrimental effects of micro-gravity, in contrast to centrifugal force, as a substitute for gravity; with specificity on duration and frequency.

[@Mionikoi]

It sounds like a lack of gravity issue? Maybe before we do long hull space trips, we push for centrifugal-gravity and at least have something for our astronauts' sleeping quarters. I would suggest a modular design with a gradual direction being toward a complete living habitat that doubles as a work space. Eventually, space stations and colony ships could have this standard.

[@ebonstone2980]

To boldly go where our eyes fold and wrinkle...

[@careless3241]

I'm pretty sure having microsized things tearing through you like the types of energy and radiations that our atmosphere protects us from, would do some form of damage, especially to the inner workings of your eye lenses

[@narltoffle]

me as an astronaut: wow space is cool, why do my eyes hurt though another astronaut: oh yeah SANS is pretty rough on the eyes SANS: maybe its the way you're dressed

[@NavajoNinja]

*alien points at eyes "This is what happens!"

[@ninjaswordtothehead]

I would attribute most of this to "We are not supposed to be here." Same as why you catch on fire in a volcano and get crushed if you go too deep in the water.

[@johnnydjiurkopff]

If I had to take a guess before even watching the video, I'd wager something along the lines of an excess of a specific wavelength of either ultraviolet or infrared light that typically gets filtered down to more healthy levels for our eyes by the Earth's atmosphere and that we haven't identified specifically as harmful is getting reflected throughout the cabins.

[@jonrios1389]

*Reads title* Me: Really? We REALLY don’t know? Are you sure?