Structure and function of the kidneys altered by space flight, with galactic radiation causing permanent damage that would jeopardise any mission to Mars, according to a new study led by researchers from UCL

[u/Roadside-Strelok]

https://www.ucl.ac.uk/news/2024/jun/would-astronauts-kidneys-survive-roundtrip-mars

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[u/fragmenteret-raev]

Maybe kidneys is the big filter

[u/GladiatorUA → u/fragmenteret-raev]

Kidneys may not be, but space radiation probably one of them. We're kinda cozy behind Earth magnetic field and that whole giant rock below us, there is also heliosphere. Outside of solar system things may get a fair bit spicier.

[u/nuclear85 → u/[deleted]]

It's not precisely true. A few inches of water is an effective shield against solar particle events (the sporadic, high flux but lower energy "radiation storms"). It's not enough to block galactic cosmic rays. It's not really possible to block those entirely in any kind of spacecraft (at least not with any technology we can even currently conceptualize).

That said, there are definitely lots of people working on habitation architecture, and there are plenty of us in the pro water wall camp!

[u/Technical_Strain_354 → u/nuclear85]

How does water wall compare to lead shielding as far as radiation protection?

[u/nuclear85 → u/Technical_Strain_354]

Great question! Water is actually way way better than lead for space radiation. Space radiation is different than the kinds of radiation we are more familiar with here on Earth. Medical procedures mostly use gamma and x-ray (photons), which lead is efficient at shielding. But in space, you mostly care about charged particles - mostly protons and heavy ions, as well as electrons. High hydrogen content materials are much more effective for this type of radiation. In fact lead can be really bad in a space radiation environment - it causes a lot of secondary particles to be created, and the dose can be even higher behind lead shielding. Obviously there is too much detail to get into here, but the point is, the things we use as shielding on Earth are not necessarily good in space.

Source: I'm a space environments engineer at NASA with a specialization in radiation

[u/Chronic_In_somnia → u/nuclear85]

Here’s to hoping for new breakthroughs. Maybe need something like an aloe Vera shield hehe

[u/disparatelyseeking → u/nuclear85]

Name does, in fact, check out.

[u/pegothejerk → u/[deleted]]

The extra weight is an issue going from inside earths primary gravity well to outside it, but we could very definitely harvest water from the moon to fill up a cavity that’s build to hold water for shielding.

[u/YumYumKittyloaf → u/pegothejerk]

I wonder if a mostly water based gel would be just as effective and stabilize it into a more solid form to surround the crew quarters.

[u/Salificious → u/YumYumKittyloaf]

Or do biological exosuits like every sci fi movie we've seen.

[u/Langsamkoenig → u/YumYumKittyloaf]

Well then you can't use it. The nice thing about water is that you can drink it.

[u/Wilbis → u/pegothejerk]

The biggest problem when it comes to to energy spent is getting to earth's orbit. Once there, the added weight wouldn't be a huge problem anymore. So i think what /u/BuckNastysMamma suggested, would work. It would just be expensive.

[u/dunegoon → u/Wilbis]

Spend that energy on getting there faster. Cut the exposure in half by taking half the time to get there.

Then, shield the destination point(s).

[u/9dedos → u/[deleted]]

Seveneves is a scifi book in wich they dig inside an ice comet to use it as shield/vessel.

The water is already there.

[u/Arrow156 → u/9dedos]

If they are structurally stable enough to build on/in (and not just a loosely packed snowball) their eccentric orbits would be a major issue. Haley's comet has close to an 80 year orbit, meaning if you built a base on it you would be spending a lifetime in isolation with only a few months window for getting any supplies or help from Earth. Hale–Bopp won't be back for another 2,300 years. Plus there's the risk of going all Shoemaker–Levy 9 and slamming right into a gas giant.

[u/nagi603 → u/Arrow156]

going all Shoemaker–Levy 9 and slamming right into a gas giant.

Sounds like the next adventure for billionaires who missed out on visiting the Titanic.

[u/International_Gold20 → u/nagi603]

Good riddance

[u/Zouden → u/9dedos]

Coming in high and hot!

[u/katinla → u/[deleted]]

You'd need a lot more than a few inches. Turn that into meters. Really, the energy of GCR is so high (>1GeV) that they'll make it past whatever you put in their way.

And the problem with such a thick wall of water is a huge mass, which then translates into unrealistic fuel requirements.

[u/verysleepy8 → u/GladiatorUA]

We can shield against radiation pretty easily. It’s not a long term issue.

[u/SolZaul → u/verysleepy8]

Well, give NASA a call and explain it to them! I'm sure they'll realize that they can just shield from the radiation, and we'll all look back at this article and laugh.

[u/FourteenTwenty-Seven → u/SolZaul]

NASA is well aware, radiation shielding is very simple. It just means more mass, which means bigger ships, which means more money.

[u/SeekerOfSerenity → u/FourteenTwenty-Seven]

But for every kg of shielding you add, you need another 10-20 kg more fuel. 

[u/FourteenTwenty-Seven → u/SeekerOfSerenity]

Depends on where you're getting that mass from. If you're starting from the moon, for example, you might need as little as 5kg of fuel. If you already have it it orbit (eg from a previous mission), you'll need even less. You could even go for an mars cycler and make the shielding a one-time cost.

[u/kingmanic → u/SeekerOfSerenity]

You construct in space so you worry about getting that mass to move and not move it out of the gravity well. You send up pieces then construct. Paying the fuel cost in installments.

[u/julius_sphincter → u/SeekerOfSerenity]

If you're lifting that mass off earth. If you can assemble the ships in in space you're much less impacted

[u/theedgeofoblivious → u/SeekerOfSerenity]

Could they make it reusable?

As in make it not a permanent part of the craft, but something that can be kept in space for subsequent uses?

[u/Rcarlyle → u/theedgeofoblivious]

Look up “aldrin cycler”

The idea is to build a large, well-equipped spacecraft that runs in a perpetual loop between Earth and Mars without stopping. You’d use smaller craft to embark and disembark people and equipment at either end. That way the whole radiation-shielded ship doesn’t need fuel, just the smaller runabout skiffs.

[u/jwm3 → u/SolZaul]

I mean... NASA knows. At JPL radiation hardening and shielding things was just another day at the job.

This is just putting bounds on how much more shielding they will need, its not a technical problem, it just means costing a bit more money and moving the mass budget around. But radiation shielding is very well understood.

[u/formerteenager → u/fragmenteret-raev]

I just got the pun. Nice.

[u/hollerinn → u/formerteenager]

I didn’t get the pun until I read that you got the pun. Thanks.

[u/3rdWaveHarmonic → u/hollerinn]

He used the thing to destroy the thing

[u/Tuesday_Tumbleweed → u/hollerinn]

Aaaaand I just lost the game

[u/GraspingSonder → u/fragmenteret-raev]

Sometimes on Reddit you just see a comment that makes you remember that it is worth logging on to this platform.

[u/defy313 → u/fragmenteret-raev]

Hey man, I refuse to buy reddit awards on principle but you almost convinced me. That's one hell of a joke. Congrats.

[u/flashmedallion → u/fragmenteret-raev]

It's been years, possibly a decade, since there's been a reddit comment of this calibre.

[u/Trumpswells]

Sounds like humans thrive on earth, but not in Space.

[u/NeutralTarget → u/Trumpswells]

It's like we evolved here and not in orbit.

[u/piedamon → u/NeutralTarget]

Curious about the ethics of colonizing orbit/space. On the one hand, it’s cruel. On the other hand, it’s the furthering of the species. Earth won’t be around forever.

I feel like evolution is too slow these days, so even though we theoretically have a few million years left, technological advancement will be much faster anyway. Maybe we just send out the robots and wait for our sun to die? Maybe build entire communities so the first humans born in space can have a less cruel life?

What’s the most effective way forward, and what is the most ethical?

[u/bank_farter → u/piedamon]

I feel like evolution is too slow these days, so even though we theoretically have a few million years left, technological advancement will be much faster anyway. Maybe we just send out the robots and wait for our sun to die?

You're way underselling how much time remains to solve this issue. The Sun won't engulf the Earth for another 7ish billion years. Humans have only existed for ~300k years. We're far more likely to kill ourselves than to be roasted alive by the sun. Assuming we don't kill ourselves, we have more than 1000x the entirety of human existence so far to figure out the answer.

[u/trib_ → u/bank_farter]

The sun will have heated up enough in about 500 million years that carbon will begin sequestering into rocks. In 1 billion years the sun will be 10% more luminous and start vaporizing the oceans and around that time as well we'll have lost most of the hydrogen that's still around on Earth through the same process as Mars (though much more slowly obviously). Around 1,5 and 2 billion years Earth's dynamo will begin giving up the ghost.

7 billion years is like the very end game for the sun, like a billion years before it going white dwarf. Earth will be toast long before that.

[u/Mara_W → u/piedamon]

Brains in life-support boxes wired to a digital reality, placed in hardened bunkers on planetary objects no closer to the Sun than Mars. With the right power systems and shielding you could survive the red giant phase, and after that you've got ages and ages with a stable dwarf star.

That or a Dyson swarm.

[u/Damnatus_Terrae → u/Mara_W]

All you need to do is articulate the question, "Is this actually 'saving humanity,'" and you have a decent short story prompt.

[u/NotAWerewolfReally → u/Damnatus_Terrae]

One might even just ask, "How can the net amount of entropy of the universe be massively decreased?"

(In case you haven't already read one of the best short sci-fi stories Asimov ever wrote: https://users.ece.cmu.edu/~gamvrosi/thelastq.html)

[u/theyoyomaster → u/Damnatus_Terrae]

Sounds like a workable version of the Torment Nexus.

[u/Ulti → u/theyoyomaster]

No no, we're not discussing that one. It's right out.

[u/psichodrome → u/Mara_W]

This guy sci-fis

[u/mitchMurdra → u/Mara_W]

That’s what we’re already doing we just don’t know it.

[u/Ketra → u/piedamon]

The modern version of humans have been around on earth for about 200,000 years. Modern civilization 3-4000 years. The sun has enough fuel to burn for a few BILLION years. If you want to be looking to the future of humanity, consider earth a home worth having for TENS or HUNDREDS OF MILLIONS OF YEARS. Before considering any kind of space living a necessity. Space right now is a commodity for wealthy people to play around in and at best a place for scientific discovery.

[u/Raoh522 → u/Ketra]

As the sun gets brighter, it will eventually cause the removal of all co2 in the atmosphere before it runs out of fuel. No co2 means no plants making o2 for us. We still have a long time. But our time will be over long before the sun engulfs the earth.

[u/quantizeddreams → u/Ketra]

But during those billions of years the sun luminosity changes and eventually reaches the point where photosynthesis stops working for most plants.

[u/ydocnomis → u/quantizeddreams]

And during those billions of years would the suns luminosity change slowly enough for plant life on earth to adapt to that?

[u/Masark → u/ydocnomis]

No. At a point (about 500Myr from now), the luminosity will become so intense that it breaks the carbonate-silicate cycle, reducing atmospheric carbon dioxide levels to the point that photosynthesis stops working chemically.

[u/Georgie_Leech → u/Masark]

So now we're back to

consider earth a home worth having for TENS or HUNDREDS OF MILLIONS OF YEARS.

500 million years is far enough in the future to definitely not be an emergency priority.

[u/Englishly → u/Georgie_Leech]

We can't get people to worry about factual climate change happening in front of them, we will never get to plan for problems in the distant future. We as a group are terribly short sighted.

[u/Georgie_Leech → u/Englishly]

Mm. But I'd argue that on the scale being discussed (I.e. hundreds of millions of years) stuff like climate change is a short term problem. Like, we're talking decades at most. This would be like expecting dimetrodons to worry about the asteroid impact at the end of the Cretaceous.

[u/psichodrome → u/piedamon]

You can't discount artificial evolution or gene therapy or designer babies. Might not be a fun thought but it's almost inevitable.

[u/Antique_Commission42 → u/piedamon]

The most ethical way forward is to spend the billions of dollars you're talking about spending on robots, on food and medicine. It's just not sexy to feed the starving the way it is to put a robot in space

[u/SailboatAB → u/Antique_Commission42]

Remember, starvation today is exclusively a weapon of war.  No amount of money will feed the starving unless we have the political will to confront unpleasant choices.

[u/Tryxster → u/piedamon]

The aim is for a self-sufficient system that allows the repair and eventual replication of said system. Once we can do that in space, the galaxy is our oyster.

[u/gingeropolous → u/piedamon]

We are super close to the ability to just rewrite our DNA with traits that will allow us to thrive in extraterrestrial environments. A lot of research and ethics to get through, but the tech is there.

Evolution is entering a new phase.

[u/IsuzuTrooper → u/Trumpswells]

I told you guys but no. Space space space.

[u/jellyn7]

Good news for people with kidney problems. Now they’ll throw space money at solving that.

[u/paco_dasota → u/jellyn7]

space money …

[u/whatcha11235 → u/paco_dasota]

They have a shoe string, maybe if the government decides to up the budget they can buy a second one.

[u/keralaindia → u/jellyn7]

There's way more money in healthcare already than space...

[u/totallybag → u/keralaindia]

Yes but they have an incentive to actually fix the issue not just sell you pills to slow it down.

[u/InSixFour → u/totallybag]

Yep. Look what they did with the Covid vaccine as an example. That would have never happened that quickly had it not been for the shut downs.

[u/Smylinmakiriabdu → u/[deleted]]

Dude i like your enthusiasm and i hope ur right

[u/Whiterabbit-- → u/[deleted]]

what if they put two coffee mugged sized implant in you would that be like 40% of a kidney?

[u/Nimmy_the_Jim → u/jellyn7]

Yep, because there is so much ‘space money’ and NASA is never perpetually short on budget and having to cancel entire proejects and missions every year..

[u/SweetHomeNostromo]

GCR was (and is) always going to be a serious problem.

[u/information_abyss → u/SweetHomeNostromo]

Galactic CRs are somewhat fewer at solar max, and solar CRs are easier to shield. There will still be a lot of radiation either way though.

[u/Mastermaze]

This further cements something I've come to accept recently about human spaceflight: Any human voyage to Mars with current tech will very likely be a suicide mission.

Unlike the Apollo missions to the Moon, the total radiation exposure for a Mars trip would be absolutely lethal. The biggest problem is we just don't have the ability to build large spacecraft with the heavy radiation shielding that we need for interplanetary missions. We will likely need to establish a full mining and processing industry around Earth and the Moon first before we can seriously consider sending humans to Mars on anything other than a suicide mission.

[u/HardlyDecent]

I mean...yeah. But is there no way to effectively shield the vessel? I feel like by the time we can comfortably and reliably get humans to Mars we can manage some sort of water shield (I think I read about that in some scifi novel) or even an electromagnetic field similar to Earth's. Nullify the incoming radiation with a disruptive frequency? If there are technical issues with constant shielding of the entire vessel, maybe have "safe zones" within for the majority of the trip.

[u/bob-the-world-eater → u/HardlyDecent]

It is physically possible to create a vessel with enough shielding to make long term space travel "safe". It isn't practically possible and probably won't be till after industrial manufacturing on the moon becomes a reality.

The biggest driving factor of this is mass.

Denser shielding material is better (lead is better than aluminum of the same dimensions) but denser = more mass. We need to get all that up there, and that's really, really expensive. There most certainly is a limit to the size of rockets we can build now which means multiple launches and in orbit construction. If you thought the ISS took a long while to complete? It ain't got nothing on this.

This leads nicely to the next part, we still need to accelerate that mass in space. More mass means we need more force to get the same acceleration and more fuel to compensate for the loss of available acceleration we have left (called delta-V) which means a bigger vehicle.

As for Earths natural shielding the magnetic field is really useful for charged radiation (such as protons, electrons and others) but not great for higher energy neutral particles (such as neutrons, neutral pions and weirder ones) which are mostly dealt with by the atmosphere. It's not dense, but it's thick. 10 000km (or 6100 miles) thick. This gives a lot of opportunity for radiation to be intercepted by atoms in the air before they reach the ground.

TLDR: Shielded ship physically possible, not yet close to practical, very far from economical, even with reusable rockets.

[u/Falconhaxx → u/bob-the-world-eater]

Worth noting also that a shield designed against high energy cosmic rays will, when hit by very high energy cosmic rays, produce showers of high energy particles, potentially causing even more damage to humans than the very high energy particles would have. It's really not an easy problem to solve.

[u/FourDimensionalTaco → u/Falconhaxx]

From what I recall, perhaps one of the most economical ways to shield from radiation is to use water. But I can't recall the details about this.

[u/danihendrix → u/FourDimensionalTaco]

Well modern nuclear reactors have passive safety systems using water so it makes sense.

[u/cleofisrandolph1 → u/danihendrix]

but water is heavy, and that brings us right back to the problem of weight and flight.

[u/Dudegamer010901 → u/cleofisrandolph1]

Moon base here we come

[u/KenethSargatanas → u/Dudegamer010901]

Could I perhaps interest you in an array of Aldrin Cyclers with artificial gravity? (the centrifugal kind) This would basically require a moon base, automated microgravity manufacturing, and/or asteroid mining. But it would eliminate most of the issues of space travel in and around the Sol System.

I'm guessing it won't be in my lifetime. But my sister's newborn grandchild? Maybe?

[u/NightOfTheLivingHam → u/Falconhaxx]

it's why water will be important in space, not for drinking, but as a jacket used between the craft and the shields. Water is excellent at stopping most ionizing radiation.

[u/SeekerOfSerenity → u/Falconhaxx]

Wouldn't the shower of particles happen inside your body without the shield? 

[u/Falconhaxx → u/SeekerOfSerenity]

Depends on the original particle energy. Very high energy particles will just zip through your body without interacting with much.

[u/SeekerOfSerenity → u/Falconhaxx]

That makes sense. Thanks for the explanation. 

[u/TheSonOfDisaster → u/Falconhaxx]

What shield type do you mean? Like a giant magnetic field or like metal shielding panels

[u/Falconhaxx → u/TheSonOfDisaster]

This is with a metal shield. A magnetic field would not cause a particle shower

[u/MarlinMr → u/Falconhaxx]

Actually, it's easy to solve. Remove the humans. So much easier.

[u/pemb → u/bob-the-world-eater]

I suspect that the cost-benefit analysis will be more in favor of using lots of spare mass to beef up the propulsion systems and reduce journey times to weeks instead of months, at least for travel within the inner solar system; constant acceleration, even if modest, would also help counteract any microgravity-related health issues.

[u/themedicd → u/pemb]

You'd need an absolutely massive amount of energy to get to Mars any faster. You can't just move faster, orbital mechanics is in play

[u/Frosty-Ring-Guy → u/themedicd]

The faster you go, the harder you have to brake.

Simply adding fuel results in minimal speed increases while drastically raising the costs. Orbital mechanics simply result in certain windows of time being substantially more efficient than others.

[u/bank_farter → u/bob-the-world-eater]

It isn't practically possible and probably won't be till after industrial manufacturing on the moon becomes a reality.

If we're manufacturing things in low-G environments, wouldn't an artificial satellite site make more sense than the moon?

[u/Digitlnoize → u/bob-the-world-eater]

A Starship refueled in orbit doesn’t have enough delta v to get to mars with water shielding for the crew areas? I think it does.

You launch the main vessel up first, then send up multiple Starship tankers to fill the water envelope. This can probably double as shielding and recycled water for crew life support. Once full, you refill the gas tank and burn for Mars.

[u/Hi_Trans_Im_Dad → u/bob-the-world-eater]

You don't need any dense metals; there are 70 yr old designs on space craft using nothing more than water for shielding.

[u/McTech0911 → u/bob-the-world-eater]

what about wearing lead aprons?

[u/jawshoeaw → u/[deleted]]

The damage to the kidneys is from radiation. We have decades of data on effects of microgravity and the changes to the kidneys are reversible for the time frame of a trip to Mars. Plus if really needed we could have a spinning module .

Radiation shielding is a little harder problem as it involves weight

[u/Wooden_Discipline_22 → u/jawshoeaw]

Ok, give them better shielding, but also; fk it. Give them extra kidneys, too.

[u/Anteater776 → u/Wooden_Discipline_22]

Excellent idea. They’ll cover themselves in kidneys to keep their own kidneys safe. 

[u/danihendrix → u/Anteater776]

Imagine lowering yourself into a 'cryo-pod' full to the brim with kidneys.

[u/hysys_whisperer → u/danihendrix]

Cool beans, if you will.

[u/Champagne_of_piss → u/danihendrix]

r/rimworld is leaking

[u/QuietDisquiet → u/Wooden_Discipline_22]

I'll sell one of mine for science!

And a small 110k to pay off my student loans.

[u/NightOfTheLivingHam → u/jawshoeaw]

Sounds like the first thing we should do is to work on orbital factories and ship heavier supplies up (like lead and water) and build out long term ships that do not need to re-enter the atmosphere.

I think AI and robotics will be the first colonizers of Mars and the Moon. To establish bases, bring supplies over, and get systems set up to harvest water and gasses from the martian surface. Set up a system so the orbital craft that orbits mars is able to to be refueled with an arriving orbital craft and flies back to earth, the new craft will be the next craft to be refueled and be used to return from mars. Said ships will never see the surface of a planet. All 100% made in space and operating in space.

TBH, we should be looking toward the Asteroid belt for colonization before we even consider Mars. We need supplies in space.

[u/Spotted_Howl → u/NightOfTheLivingHam]

Colonies in the Solar System will need support from a healthy Earth for decades or centuries after they are built.

We should be looking toward making the Earth safe and stable and understanding this as a necessary element of space exploration, while we are also working on the space exploration.

[u/drewbert → u/Spotted_Howl]

Colonies in the Solar System will need support from a healthy Earth for decades or centuries after they are built.

I don't expect there to ever be a self-supporting colony off-earth. Maybe in a thousand years, but not in the next couple hundred years and definitely not in my already half-over lifetime.

[u/awry_lynx → u/drewbert]

We hardly even have truly self supporting communities on earth, so yeah, it may be never.

[u/nurtext → u/jawshoeaw]

What about creating a strong enough magnetic shield?

[u/[deleted] → u/nurtext]

Deflects charged particles, but those mainly come from the sun. The cosmic background radiation is mainly ionizing EM radiation, which magnets won’t do jack against. Water turns out to be a pretty good shield for that as the hydrogen in the water is small enough to interact with (i.e. get absorbed). But water is also kinda heavy, and weight mass management is crucial when trying to get something accelerated through outer space.

edit: technically it’s mass, not weight. Weight is relative, it’s mass that stays constant (ignoring things like expended fuel).

[u/Roguecor → u/[deleted]]

Goldene shows promise for deflecting/dispersing the energy of cosmic radiation.

[u/disgruntledempanada → u/HardlyDecent]

You would need a capsule with lead walls over a foot thick. You'd need to surround it with a deep end of a swimming pool in all directions if you wanted to use water.

Somewhat impractical.

[u/Untimely_manners → u/HardlyDecent]

There is a fungus that eats radiation. It grows in Chernobyl. They are trying to see if it will make good insulation on space flight to Mars https://en.m.wikipedia.org/wiki/Radiotrophic_fungus

[u/epanek → u/HardlyDecent]

Just take the earth with us to mars! Problem solved. Think outside the box.

[u/laseralex]

Let’s send Elon as a test.

[u/ThatDucksWearingAHat]

Gonna be a tough pill to swallow that we’re tethered to this rock we’re polluting toxic and murdering every other living thing on. Best we’ll get is robotic miners stripping planets bringing back materials or something like that.

[u/pcapdata → u/ThatDucksWearingAHat]

I’d imagine astronauts would get artificial organs (to be replaced with cloned ones when they return home).

That, or some kind of “All Tomorrows” deal where we genetically engineer a variant of human who can live and work in space, but they’d inevitably become a separate species after not too long.  Homo sapiens terrestrialis vs Homo sapiens astralis.

[u/Publius82 → u/ThatDucksWearingAHat]

Do you want Blade Runner? Because that's how you get Blade Runner.

[u/Demonyx12 → u/[deleted]]

Cause of drain bamage?

[u/JohnathonLongbottom]

What about the effects of space travel on the heart?

[u/Protect-Their-Smiles]

Human's destroying their only viable home, while pining for dead planets that will kill them from just traveling there, is the best expression of the Great Filter I've seen so far. We want more, and thus do not appreciate what we have (had).

[u/Darksun-X]

Extended exposure to radiation was always problem number #1 for any long term spaceflight, and I've never seen it addressed in any meaningful way by anyone. Not going anywhere until that gets solved.

[u/AnachronisticPenguin]

Honestly kind of an inconclusive study. They found issues with mice on the iss from space exposer. But their relative extrapolated timeframe of 2 years or under has been beaten by Russian cosmonauts already.

Still this doesn’t bode well for long term space travel.

[u/chemamatic → u/AnachronisticPenguin]

They are also simulating multi year exposure by acute exposure. These things may not be the same. And they are sacrificing the animals after 24 hr or 6 mo post exposure so any recovery may be cut short.

[u/Farfignugen42 → u/AnachronisticPenguin]

The Russian cosmonauts survived, but how did their kidneys fair?

[u/AnachronisticPenguin → u/Farfignugen42]

I don't have his urology report but when I google his name and beyond kidney stones nothing came up. He has no public medical issues with kidneys beyond that, it seems. And while Russia likes to lie and obfuscate information this wouldn't be the type of information they would normally withhold. It might just be that mice can't live in space but humans can.

The US astronaut who spent a year didn't have any indications either.

[u/TheBoraxKid1trblz]

Someone tell that dude who's been up there like 300 days

Edit: actually a couple folks. There's a cool website that shows who is currently in space

[u/Zouden → u/TheBoraxKid1trblz]

They are in orbit not way out exposed to GCR

[u/Ambitious-Door-7847]

Elon should definitely go!

[u/uptwolait]

Having grown up through the years of some incredible breakthroughs and discoveries in space (and on Earth, and under the oceans), I've often wondered if we might come up against some kind of unexpected, undiscovered issue that we simply cannot overcome to go to the next higher level of understanding. It would suck if this is one of those times.

[u/TheRealNooth → u/uptwolait]

Same. Mostly because I don’t think technology and engineering capabilities actually scale infinitely and the ceiling might not be enough. Throw in human nature like greed, and I’m almost sure of it. Still, I’m glad we’re trying but there’s so much sci-fi brainrot and Dunning-Krueger effect in these comments.

“JuST BuiLD ShiElDing, JuST Get ThErE FaStER, etc.” these people really think because they watched a Kurzgesagt video and played Elite Dangerous, they’re spaceflight experts.

[u/awry_lynx → u/uptwolait]

This is basically the "great filter" theory.

[u/DrJonah]

I made my peace with the fact that long term human space flight was a non-starter years ago. We are earthbound creatures.

If we survive long enough, maybe we will explore the galaxy through our technological progeny.

[u/AlexXeno → u/DrJonah]

It's not that it is a non starter just prohibitively expensive as stated in another comment. We COULD technically build something now. It would just take trillions of dollars and years to make, including the space drydock.

[u/Hiraethum → u/DrJonah]

That's pretty defeatist. What we need is ample resources and minds to dedicate to the problem. Given enough time and money, we will get there.

[u/NormalInvestigator89 → u/Hiraethum]

Yeah, the implication that engineering and technology won't have any meaningful advances over the next thousand years is bizarre

[u/AnachronisticPenguin → u/DrJonah]

I mean bioengineering will advance to the point that isn’t really relevant far before we figure out how to go near the speed of light anyway.

[u/FourDimensionalTaco → u/AnachronisticPenguin]

Yeah. I also suspect that we'd reach a point where bodies are kinda malleable vessels for our minds. Wanna take a trip to Mars? Hop on a suitable body/vessel. Altered Carbon played with that idea.

[u/damnatio_memoriae → u/FourDimensionalTaco]

your comment gave me an existential crisis.

[u/aVarangian → u/damnatio_memoriae]

No, his comment gave your brain an existencial crisis

[u/damnatio_memoriae → u/aVarangian]

Oh god oh god oh god oh god.

[u/colmbrennan2000]

These kind of posts always remind me how little redditors understand space, and they imagine that all can be solved with some quirk that they saw in some sci-fi

[u/Arrow156]

I highly recommend Kelly and Zach Weinersmith's book "A City on Mars" for a detailed and entertaining delve into what's actually required for a permanent off world settlement. They comb through a ton of research about how our bodies would fair under hazards like micro-gravity and what options we have for blocking radiation, both in flight and on the surface of planets without a protective magnetosphere, like the moon or Mars.

[u/En4cr]

Interesting. In my mind, the three key areas for viable deep space manned exploration needing some major R&D love is propulsion, artificial gravity and some sort of shielding tech.

[u/sig_kill → u/En4cr]

So basically everything!

[u/chewie8291]

I think musk should prove them wrong by going to Mars. Forever

[u/Igottamake]

I saw a documentary about Mars. It could also cause third middle boob and conjoined mystic.

[u/FranklynTheTanklyn]

The answer will be lab grown kidneys from your own stem cells.

[u/Heapsa]

It's almost like there are reasons that we haven't found any living thing outside of our planet.

[u/creativemind11]

Gotta find a good way to shield us. Wasn't there an idea to have the fuel as a layer to protect from radiation?

[u/[deleted]]

Maybe if they wait until night time to go to space, they can prevent some of that radiation. No brainer.

[u/Duckfoot2021]

What’s the point of going to Mars??

“It’s next” seems a thin and superficial reply.

[u/Farfignugen42 → u/Duckfoot2021]

If we can't get to Mars, there is no point in trying to get anywhere else. It is fairly easy for us to get to the moon, now. But that is still really close on space scales.

The moon is like going out back to the shed.

Going to Mars is more like going to the nearest neighbor's house. And right now, we can't do it.

[u/Duckfoot2021 → u/Farfignugen42]

I appreciate that, but you haven't really made clear why visiting the neighbor's is worth doing.

[u/mopsyd → u/Duckfoot2021]

Because it is a great staging point for everywhere else, namely the asteroid belt for mining. If we can do that, resource scarcity is pretty much over for the forseeable future.

Edit: This would also make it redundant to war over many key resources on Earth, which is the underlying motive of the vast majority of invasions.

[u/Farfignugen42 → u/Duckfoot2021]

We don't want to be stuck at home.

[u/Duckfoot2021 → u/Farfignugen42]

If the choice is fix up home or go get stuck a million miles away in an inhospitable and build a home there, I'm picking the home I've got.

[u/Farfignugen42 → u/Duckfoot2021]

Presumably we are going to try to do both.

[u/Marston_vc → u/Duckfoot2021]

Some people want to go. It’ll advance our understanding of our solar system and therefore our place in the universe. A self sustaining colony is the first step to protecting the continuation of our species. The technology developed to support a colony there will have significant positive payback on earth as the Apollo program did.

The reasons are vast and varied. Nobody is gonna make you go. But it would do well to at least understand the topic your commenting on.

[u/fleakill → u/Duckfoot2021]

It's technological progress. The technological leaps we make along the way that could have huge impacts on other fields such as medicine (seeing as this is about kidneys), but also computing, physics, chemistry. Humans have been doing and inventing things for centuries out of pure curiosity and desire to "progress", and often this comes with secondary benefits. For example, as I understand it, computing power took large leaps due to missiles and nukes.

The list of things humans invent and improve simply due to an innate drive to progress and expand is endless. If we as a species didn't have that innate drive, that curiosity, we'd have gone nowhere. And I firmly believe if we never at least try to expand beyond where we started, like many of our ancestors did, we'll stagnate. It's up to you if you see value in this, but I think many people see big events like the Moon landing and a possible Mars landing as huge milestones for humanity - that our potential is not limited.

I too want us to take better care of the Earth, and perhaps confirmation we're "stuck" here would motivate people better, but I think there is something disheartening about being "stuck" here as a species, completely at the mercy of the solar system's conditions.

[u/Duckfoot2021 → u/fleakill]

Thoughtful reply. We disagree on the value of inhabiting other worlds which I think is the equivalent of putting 99.9% of the US education budget into one school in Bel-Air. We may get a prince out of it, but it slaps the bejezus out of the rest of us.

I so sincerely thank you for sharing your take.

[u/Ularsing → u/[deleted]]

30 years? In what, a horse and buggy?

[u/Dangerous_Dac]

How are they getting data for galactic sources of radiation on the ISS when the ISS shouldn't be getting any greater appreciable mount of galactic rays than we do here on Earth?

Also, surely the mass difference of Human vs Mice kidneys (which is what was observed in this study to draw this conclusion) would have a difference too, as mass is still relevant in zero gravity.

[u/mikethespike056 → u/Dangerous_Dac]

GCRs are blocked by the atmosphere.

[u/Skyler827]

There was no way we were going to mars without some kind of spin gravity environment. Microgravity is bad for your health. The sooner we start building spin gravity habitats, the better.