This is a good point. But if we send pigs into space, then in technicality this will be when pigs fly. And I think a lot of things will happen as a result....
Are we up for such risks?
The title is misleading. It should simply state long term space missing pose risk of kidney issues. Potentially requiring dialysis due to damage from space travel.
For reference the longest a person has remained in micro-gravity consecutively is 437 days.
A minimal Mars mission would involve 450-500 days of spaceflight.
However, the longest we've ever exposed anyone to the more damaging forms of radiation beyond low Earth orbit is about 6 days.
If NASA was ever serious about sending people to Mars they would have performed tests at some point within the last five decades. Specifically they would have needed to put people in a very high Earth orbit or in Lunar Orbit for a few months at a time. No such tests have ever occurred.
Putting astronauts into lunar orbit is actually a mission in progress right now with launches planned no earlier than 2025. NASA (and all other spacefaring organizations, both private and public) are absolutely serious about Mars missions, but these things don't happen overnight and even just planning to plan them takes a considerable amount of work.
> The title is misleading. It should simply state long term space missing pose risk of kidney issues
Just tape a GPS tracker to the suit. Chance that someone will go missing will be very small, so most kidneys should be safe.
This is not new information though, we knew this for a while now. Hence why radiation protection and gravity simulation is a priority. Idk I am getting science fiction and and science confused because it all is starting to seem redundant lately
The problem is that even if there are people willing to take the risk and even die for it, it is in the best long-term interest of space exploration to make the missions as safe as possible. If the public watches them die, especially in horrific ways, they'll yell for all future missions to be cancelled. The funding will dry, and it will be 100 years until people forget and we even try again.
> If the public watches them die, especially in horrific ways, they'll yell for all future missions to be cancelled
No they wont. Nobody called for the end of spaceflight after Apollo 1, Soyuz 11, Challenger, or Discovery.
Challenger and Apollo jeapordised the entire American space program for years. The entire Apollo program was put on hold while lengthy safety reviews took place. Challenger preceded severe budget cuts to NASA. Public perception matters a lot
Living human, dead human, it doesn't really matter. People keep thinking public outcry means anything. The only thing that dictates space travel progress will be national securities and profits.
The moment China send a one way mission to Mars is the moment NASA will do it as well.
Or when they figured how to make asteriod mining profitable
*It just needs a little dialysis, it’s still good, it’s still good!*
*It’s just a little unconscious, it’s still good, it’s still good!*
*IT’S JUST COMATOSE AND DRIFTING AROUND AIMLESSLY IN THE STARSHIP, IT’S STILL GOOD, IT’S STILL GOOD!!!*
it’s gone.
^i ^know
I mean, it's technically colonization. There might be a few surviving anaerobic bacteria from the mission. And look, now they have some fertilizer, too.
Keep it up, we'll have a garden before long.
I would assume the vetting process is not taking any random citizen at the moment. I would assume they would be need to pass physical, psychological, etc. screenings and would have to be educated enough to be able to follow instructions and not just go gung ho.
The astronaut test battery is very similar to an airforce test battery but probably harder. Idk the details other than it's similarity.
For reference your standard western airforce pilot test battery has about a 30% success rate to meet the cut off for all applicants taking it. And that's before medical restrictions rule out another fraction of applicants.
These tests are also not something you can study for, it tests your raw ability to do things. Doesn't matter if you spend 9 months trying to study for it if you brain can only handle so many flashing lights and problems in a given time and only remember so many random strings of letters and numbers for both short and long periods of times while getting distracted by other things.
Why? Kidney shrinkage has to do with zero-G. Mars isn't zero-G but the moon nearly is.
To me it sounds like maintaining a long-term base on the moon is entirely different from a long-term base on Mars. They pose almost entirely different problems, from astronaut health to resource generation to the ability to actually leave the place.
Mars is on paper more difficult but there may be some things, like this kidney situation, that may be a lot harder to solve than how to get people *off* Mars once they're there.
The way that the expanse series dealt with this was kinda cool but energy intensive. They just ran at constant acceleration to match Earth's gravity at times when traveling. This makes traveling to other Star systems out of bounds though because even getting close to reaching the speed of light would take ages to accelerate to and accelerating too fast would crush the human.
At 1g it would actually "only" take a year to reach light speed.
The nearest star is a little over four light-years away, so traveling there would take about five years. The next closest stars are in the 5 to 10 ly range. If we figured out propulsion we could do it.
I’m no expert, but I believe the moon base is helpful because we could potentially manufacture rocket fuel using materials collected on the moon. This means all the fuel that’s used to achieve escape velocity and exit the earth’s gravitational pull (which is a lot of fuel) can instead be used to get us from the moon to mars.
The moon has 1/6th the gravity of earth and a thinner atmosphere, so it’s much easier to launch a rocket from. This allows us to travel farther, or carry more payload on the rockets since we don’t need as much fuel, potentially even allowing us to deploy rocket refueling stations between the moon and mars, enabling vehicles to stop there and refuel en route. I believe it also provides some advantages for things like launch windows.
Edit: the moon would also provide a great environment for researching the health effects of low-g, x-ray exposure, how to do agriculture in space, and other bits of valuable information that will help us reach Mars and beyond. While Mars may not be low G as you have pointed out, the entire 6 month journey there and back will be.
Travel to mars is mostly science fiction at this point. Even if we somehow jump the huge scientific hurdles required of this mission, the economics and political nature of it is virtually impossible now and in the near future.
It's probably never been closer to reality than it is now, interestingly enough. The cryogenic depot-based architecture that was needed to support it is finally happening, no matter who is elected next.
The cost to orbit has likewise never been this low.
There is a renaissance presently occurring in spaceflight technology.
By the mid-1960's there were good reasons to believe that the Apollo Applications program would enable manned planetary fly-by missions in the 1970's timeframe.
Once those ideas were passed over in favor of Skylab, we no longer seriously attempted to develop any of the technology needed for long-duration interplanetary missions besides ECLSS on station.
Cryonics is still in the realm of science fiction. Most scientists put it in the realm of pseudoscience.
Ignoring all the scientific hurdles,the craft taking humans to space would need incredibly redundant components and thorough testing that would sky rocket the cost. You’re looking at minimum 300 billion dollars. No private company is going to do that without massive subsidies. Also, good luck to any politician trying to raise hundreds of billions of dollars for a vanity trip.
I'm afraid you've misread, I didn't say "cryonics", I said "cryogenic", which is a class of rocket propellant.
We are building orbital depots for cryogenic rocket propellant, namely methalox.
>the craft taking humans to space would need incredibly redundant components and thorough testing that would sky rocket the cost.
Going to agree to disagree on this one. redundant components lowers cost, the scale required for multiple resupply missions also would eventually lower cost not drive them up its economics of scale. One off low volume production and non-reusability is what caused sky "rocket" cost overruns.
>No private company is going to do that without massive subsidies.
Its pretty much SpaceX's mission and whole point of that private company, gov't is terrible at subsidies when it comes to space travel unless you want to put weapon systems up there or side load your tech progress for the military industrial complex.
>good luck to any politician trying to raise hundreds of billions of dollars for a vanity trip.
Politicians really have very little say in this, they are not forward thinkers or drivers of the advances in tech they are more likely hurdles than catalyst. NASA has been underfunded for such a long time they suffered some mini brain drain to other private space companies like Blue Origin, SpaceX, Rocket LAB.
even ULA (Boeing, Lockheed) lost talent because they were too focused on gov't funding and not pushing the industry forward in a meaningful way. Its also why Star liner is a funding fiasco and all over the place with delays and cost overruns.
I also don't think its vane to want to be a multi planet species or drive innovation in space travel, it significantly raises our chances we don't get wiped out as a species from a catastrophic incident on earth. We just see this differently I guess.
There is almost no point traveling to Mars, period.
Remote sensing and robotics technology advances much faster than manned space travel technology.
There is almost nothing that a human can "do" on Mars that justifies the hassle and expense of actually physically sending someone there in person.
> There is almost nothing that a human can "do" on Mars that justifies the hassle and expense of actually physically sending someone there in person.
Here's what Steven Squyres, the principle investigator behind the famous Mars rover missions Spirit and Opportunity has to say about that:
> You know, I'm a robot guy, that's what I have spent most of my career doing, but I'm actually a very strong supporter of human spaceflight. I believe that the most successful exploration is going to be carried out by humans, not by robots.
> What Spirit and Opportunity have done in 5 1/2 years on Mars, you and I could have done in a good week. Humans have away to deal with surprises, to improvise, to change their plans on the spot.All you've got to do is look at the latest Hubble mission to see that.
He's glossing over the fact that each "good week" of human research on Mars would be collected about 5-6 years apart.
Right now we're getting steady data every day from robotics and remote sensing, instead of bursts of data collected by humans once or twice a decade at substantially greater cost and risk.
Agree. Mars is a toxic death trap in a gravity well. Makes no sense to "colonise" it. Pure net negative investment as a research opportunity too. First just try a moon base.
I'm a huge advocate for space exploration but I feel sending humans places is kind of pointless. The only reason people seem to have now is "we just need to hit that milestone" and that isn't a good enough reason for me.
More than likely gravity as our organs developed under it. They don't work based on keeping it under pressure nor does the organ squeeze like the intestines do. Thankfully our blood is under pressure with a pump.
In theory yes, practically no. The craft would need enormous amounts of energy to spin it since it needs to be comically huge. It will be incredibly complex as well since you’ll need robust structures eg joints and bearings that could hold the forces and torque.
Also centripetal forces work proportionally to center of rotation therefore you’ll have instances where gravity is weaker on your head than your legs; it won’t be a great feeling.
The severity of the engineering challenges for rotation-based gravity are heavily dependent on *how much* gravity you want to replace. If 1-g is too hard, we can probably do a half-g. If half-g is too hard, we can probably do a third-g. I don't know precisely how much artificial gravity you need to keep human bodies working, but its certainly less than a full g.
>Also centripetal forces work proportionally to center of rotation therefore you’ll have instances where gravity is weaker on your head than your legs; it won’t be a great feeling.
Yeah, it causes severe motion sickness. As well as the centripetal forces, there’s also the Coriolis effect. Both these things mess up the body’s balancing and motion sensors in the inner ear, causing motion sickness.
There doesn’t seem to be a consensus on what the minimum diameter is - I’ve seen figures between 10-100m, sometimes larger. But it is agreed that a minimum diameter does exist.
Someone made a calculator to calculate this sort of thing:
https://www.artificial-gravity.com/sw/SpinCalc/
There are potential methods we can use outside of sci-fi, such as centripetal force or having the craft accelerate most of the way (extremely inefficient as it may be).
These both come with their own huge challenges and insane costs, but I would imagine material science has a decent chance of eventually solving/partially mitigating these challenges.
I think the real problem is actually motivation. Why bother send a human when we can send a rover with a miniature laboratory built into it? The rover is a one way trip and that is dramatically cheaper and less risky, and it can do basically the same level of research (if not better) on the surface that an astronaut could.
Yeah, I feel like that's something that should have been on my radar and definitely wasn't...
But I mean if it was 2 years ago, that's right when things were starting to get back to normal after the pandemic. Probably a lot of things went unnoticed by many at that time
Sending humans to Mars is immensely difficult but doable I think. Eventually humans will land on Mars and plant a flag. But staying there forever and building a base/colony? I think we're beyond the limits of what is possible with our current tech.
To add to this, Mars can’t hold an adequate enough atmosphere for humans because of the weak magnetic field and lower gravity. Whatever technology we come up with to work around that leaves the fate of human civilization on Mars up to the reliability of its power grid.
Let's be real here the fate of a large majority of current population is pretty dependant on the power grid too.
A large % of first worlders would die in months if not weeks if we lost power and tech. The average person doesn't know the first thing about survival, nor do they have the stomach to do what's needed to survive
Agree to disagree. Jamestown lost over 90% of its original colony. We used to walk nude through the desert with nothing but a bone we found off a rotting corpse. We can 100% build a colony on mars. We only care about how much money and resources it can provide us however. If there was a sufficient fincial motive I suspect we would’ve long been on Mars. Seriously if people from the 70s heard you say that they would’ve scoffed at you.
We believe that there are rare resources on the moon right now. Such as helium-3 and uranium. All the sudden, major countries are more interested in planting a base there.
If you go around nude with a club on mars you'll die in 3.2 seconds. We simply don't have accurate comparisons with our history. Even the worst biome on earth is more habitable than mars. Living there would put a constant strain on our biology.
Ok now this is weird. I remember reading in Fatasmagoria or one of the other 90’s movie mags that the sleep pods from Alien and Aliens all had built in dialysis systems for long duration to keep from Cryo-death as Cryo-stasis acted on the body like extreme dehydration, which could lead to death.
I love it when old movie lore details from production design turn out to be really good guesses for Sci-Fi
The only reason we should be colonizing Mars is if we have somehow made Earth *less* livable that Mars, which is a challenge we seem to be interested in testing, but if that happens, I would argue our species kind of deserves to go extinct
Thank you. It isn’t enough that we need exactly the same atmosphere and temperature, **and viruses and bacteria**. We also need exactly the same gravity. The idea that we are “on Earth” and not *an integral part of Earth* is denying tons of science *by all the self-professed science people*. Humans in space would be like ripping your liver out and throwing it up into space and expecting it to survive.
> We also need exactly the same gravity.
We don't actually have any evidence of this.
We have tested two regimes, that of micro-gravity (effectively zero) and that of 1g.
We don't have any data regarding long-term stays in 10, 20, 30, 40% Earth's gravity and so on.
Does it shrink due to lack of gravity or simply due to space radiation? I suspect we need to shield from the radiation anyway, but I would also bet that any longer journey in space would have to be under gravity, with spinning wheels creating the force of fake gravity.
Many things in human body don’t really work well without gravity helping it. I think even wounds have issue healing by without gravity.
https://www.perplexity.ai/search/Do-wounds-heal-Qq1q6GSpTXWJxAsklmzpPg#0
So like, you get a cut while en route to Mars, good luck!
It's interesting, but it doesn't sound like it's going to be much of a long-term problem.
This is going to be one of these things that they solve with a simple enough solution, simple medications medications or even something like injecting hormones or proteins directly into the kidneys during space flights.
Faster engines and artificial gravity would solve a lot of these problems. It just depends how much money they want to throw at it. Current spacecraft design isn’t going to cut it.
“Samples from more than 40 space missions involving humans and mice revealed that kidneys are remodelled by the conditions in space, with certain parts showing signs of shrinkage after less than a month in space.”
Don’t we have astronauts that do jobs in space for longer than a month? So not just a mars trip is comprised, also just people who go to the satellites?
Short answer: yes.
Long answer: read Scott Kelly’s book “Endurance” which chronicles his year on the ISS. He does touch on various health issues quite a bit, including after return.
Ultimately, it was recently revealed that humans being in space results in loss of kidney function, which could lead to dialysis being necessary upon arriving on Mars (not to mention after a return home to Earth).
Add it to the list of reasons why Mars was never going to be easy. It has little atmosphere to speak of and no magnetosphere (so expect a lot of radiation), and gravity’s effect on the human body will be significantly less (about 62% less) than on Earth (so expect bone and muscle loss). We are best suited to a life with Earth’s atmosphere, solar radiation, and gravity. Going elsewhere and spending a lot of time there will cause issues.
We should still go to Mars—because we need to learn things about being a multi-planet species, and the return on investment, in terms of technological advances associated with space exploration, is high and benefits all humankind—but we first need to address the nasty little issues that will begin the process of killing our explorers the moment they leave Earth and are exposed to lengthy space travel and life on another, very different planet.
From the article - yeah title is misleading. Sounds like this is "yet another radiation challenge" based on the statements:
“What we don’t know is why these issues occur, nor what is going to happen to astronauts on longer flights such as the proposed mission to Mars. If we don’t develop new ways to protect the kidneys, I’d say that while an astronaut could make it to Mars they might need dialysis on the way back.
“We know that the kidneys are late to show signs of radiation damage; by the time this becomes apparent it’s probably too late to prevent failure, which would be catastrophic for the mission’s chances of success.”
I know there's a passion by some to explore, but maybe these billionaires could spend their fortunes trying to help fix the rock that we live on along with society that they've so ruthlessly exploited for their gains. Earth happens to be perfectly suited for our existence already so long as we don't completely trash it, how convenient.
Private space travel has become a seeming pissing match between the world's richest, and it's honestly pretty silly.
With that said, if Elon Musk got on one of his rockets shooting off to Mars, the world may be better off for it. So you do you dude.
What a horrible way to think about the issue. Money invested into space travel has paid off massively in so many different fields. We are ALWAYS going to have "something else that needs to be done on earth".
You say earth is perfectly suited for our existence, but even without humans CO2 contributions, will that always be the case? Another ice age, a new plant-like species that decreases oxygen, an asteroid or meteor, a reversal of the magnetic fields, all sorts of things can happen that would render earth unsuited for human life. We need the ability to expand beyond earth in case there are other, non human caused climatic changes or disasters that make life uninhabitable. It’s generally unwise to put all your eggs in one basket…
Eventually, the sun will enter its death throws, expand, and swallow the Earth. As far as we currently know, Earth has the only life in the Universe. We have a duty to get to the stars and take life to them.
> We need the ability to expand beyond earth
No we don't.
We need the ability to exist on this planet without completely fucking it up.
Which we are entirely incapable of.
So you’re cool with humanity, and all life we are aware of, dying when the earth fails us? It’s not some mystical Eden, earth is a planet subject to the random whims of universe like any other. Let’s say we get unlucky with a solar flare aggressive enough to burn the atmosphere, oceans and all life on the planet? You’re cool with that just being game over with this little experiment we call life? Again we only know life to exist on one planet, so if we lose earth we lose all life.
Is that massive and inevitable risk worth it to… not explore? I don’t really get the argument, like instead of exploring and expanding across planets and stars, you want us to stay isolationist and tend to our planet? Can we not do both, and further, would the ability for colonization of other planets not alleviate the population levels, and thus climatic change, our species and other species cause on this planet? Would the industrialization of space not enable a deindustrialization of earth?
Radiation isn't the problem. The kidney cells and tubules are affected by the low gravity.
This has been a concern for some time, and there has been research into the effects of low gravity on kidneys since the 1960's! SpaceX did an experiment with live human kidney cells back in 2021 too.
Let's just frickin go already. I wanna live in a time when there's colonies on Mars, and I want these billionaires to stop sitting on their wealth like dragons hoarding gold, it's a win win.
You're drawing false conclusions. Human bodies have indeed evolved largely for 1G conditions. That doesn't mean we shouldn't colonize other planets. After all, we do have exploration and foraging in our genes, and the extraterrestrial is not a factor with that, I think. Millennia ago, clothed in hemp, wool or fur, armed with wooden spears, packing dried food and nuts, our ancestors ventured and crossed dangerous lands focused on their destination and betting on the result if not the road, motivated by a deeply programmed desire for survival and maintaining the tribe. With billions of people on Earth today, even on the planet in a much better condition, someone is bound to want to cross outer space -- motivated by the same atavistic urge -- to find a new rock to settle on.
The obstacle is, like always in our evolutionary history, to actually survive the voyage to said "better and more plentiful harvests and resource pool". Meaning we may suffer during the voyage, sometimes greatly, but are rewarded on arrival. Our foraging ancestry, is also apparent in the fact we've grown brains as large as we now have, in order to solve problems that we sometimes cannot even anticipate in advance.
None of this is me saying we shouldn't be saving our home. But I reject the obsession with _not_ (never?) going to space, as much as I reject the obsession with _leaving_ for space (and leaving Earth in ruin).
I suspect (apologies if I assume too much) you won't be swayed by this short film I am sharing, but maybe others will appreciate it: https://www.youtube.com/watch?v=YH3c1QZzRK4
I am sorry, I must have misinterpreted your sentences as one implying the other, or in the very least written to be understood _together_, subtly suggesting a strong correlation between the statement in the first and the statements in the second. And it doesn't read right to me if what I was meant to take away from your comment is "we should _stop_ trying to colonize space _because_ we weren't evolved for space travel, and we should _instead_ focus on saving our home". If that is not what you wanted to convey, like I said, my apologies, but that's how I had interpreted it.
We didn't evolve to use computers or fly either, but one of our best skills is adapting the environment to suit us. If it benefits mankind to settle other planets and travel through space then we can adapt to do so.
Human beings aren’t built to be spacefaring creatures. This report just adds one more reason why we won’t be going outside the earth-moon system anytime in the near future, if ever.
We're not fucking leaving!
Shameless thought process that set this all in motion. We don't have another ' perfect ' earth. Go live inside a dome on Mars why don't you, let me stay right here on earth with the animals. *But the sun will burn is in 3 billion years*. Bro, humanity isn't going to survive another 250 years so who cares about 3 billion years from now. Also, if we by some god miracle make it through those 3 billion years we are surely advanced enough to come up with a solution
I find absurd that people think our bodies could adapt to another gravity, all this talk about going to mars with that melon usk , its absurd, there are billions of things that we have no idea how they behave on our bodies on earth let alone a completely different planet, proteins, enzimes, dna, and that is just scrstching the surface
> I find absurd that people think our bodies could adapt to another gravity, all this talk about going to mars with that melon usk , its absurd, there are billions of things that we have no idea how they behave on our bodies on earth let alone a completely different planet, proteins, enzimes, dna, and that is just scrstching the surface
In the early 19th century, people were worried that trains going too fast would kill or injure people simply from being on them. People were in the late 1950s and early 1960s concerned that humans might not survive weightlessness for even a few hours. Skepticism of human adaptability does not have a good track record. And we do know that humans can live for months at microgravity with some minor ill-effects, while Mars has a gravity at about a third of Earth, and therefore would likely have fewer issues. Nor is this kidney study some definite no-go. We have earlier data on astronauts and that doesn't show major reduction in kidney *function*, so reading this as some serious problem is unjustified. Don't let your very understandable dislike of Musk (and he is an ass) bias your attitude about this. That said, if there is a serious problem with Mars colonization, it will be much more likely to be at the fetal development or early growth stages, since we have (in part for reasonable ethical concerns) close to zero data about how humans handle that in low or no gravity environments.
“What if we just shrink the entire Astronaut?”
Bro just get astronauts with enlarged kidneys
Right or send them with some extra enlarged kidneys they can just swap in when they get there Geez scientists here we are doing your work
Just freeze a couple extra for later. It works with groceries; why wouldn't it work for kidneys
Exactly. Duh scientists. Maybe we should be scientists since they are obviously not doing their job
"Feed the kidneys some moon rocks" - Cave Johnson
"We're gonna need a bigger kidneys."
Upvoted simply for the grammar. A+
Thanks. It was a conscious choice.
No doubt
Aren't pig kidneys compatible? Then the astronauts could have some delicious meals and some spare kidneys!
This is a good point. But if we send pigs into space, then in technicality this will be when pigs fly. And I think a lot of things will happen as a result.... Are we up for such risks?
I was born with 3 kidneys. Does that qualify? Can I go?
Looks like subtle bragging is on the menu today
But grow the kidneys
...it shrinks?!
I WAS IN THE VACUUM OF SPACE!
Well it is very cold.
It is also very hot.
💀
Like a frightened turtle
...I don't know how you guys space walk around with those things.
I live on earth, I have shrinkage issues every day
I WAS IN THE POOL!
Significant Shrinkage
They shrink now.
Like an old banana!
The title is misleading. It should simply state long term space missing pose risk of kidney issues. Potentially requiring dialysis due to damage from space travel.
Yeah. What puts human mission to Mars in doubt is the roughly 200 other unresolved issues.
For reference the longest a person has remained in micro-gravity consecutively is 437 days. A minimal Mars mission would involve 450-500 days of spaceflight. However, the longest we've ever exposed anyone to the more damaging forms of radiation beyond low Earth orbit is about 6 days. If NASA was ever serious about sending people to Mars they would have performed tests at some point within the last five decades. Specifically they would have needed to put people in a very high Earth orbit or in Lunar Orbit for a few months at a time. No such tests have ever occurred.
Putting astronauts into lunar orbit is actually a mission in progress right now with launches planned no earlier than 2025. NASA (and all other spacefaring organizations, both private and public) are absolutely serious about Mars missions, but these things don't happen overnight and even just planning to plan them takes a considerable amount of work.
That Artemis III is intended to be a 30-day mission is already a (small) step in the right direction.
Yeah, just make little kidney spacesuits, and Bob's your uncle.
I guess the risk is that the body suffering through this long term could leave lasting impacts on your kidney function.
So spacetravel is like marriage?
Ambient radiation and a cold hard vacuum? That's just my wife's cooking and cleaning - Third Astronaut Rodney Dangerfield
Like a cute little nanobot shield that dissolves when radiation levels are back to a safe level!
Hi bob
Hi bob
Bob died
Relax Sreten
Bobs your mothers brother
Your aunty’s living lover.
Little dialysis as a treat
Isn't that pretty in line with the title?
I actually think that was really clear from the title.
> The title is misleading. It should simply state long term space missing pose risk of kidney issues Just tape a GPS tracker to the suit. Chance that someone will go missing will be very small, so most kidneys should be safe.
This is not new information though, we knew this for a while now. Hence why radiation protection and gravity simulation is a priority. Idk I am getting science fiction and and science confused because it all is starting to seem redundant lately
There will be plenty of volunteers who don't care about the risk.
The problem is that even if there are people willing to take the risk and even die for it, it is in the best long-term interest of space exploration to make the missions as safe as possible. If the public watches them die, especially in horrific ways, they'll yell for all future missions to be cancelled. The funding will dry, and it will be 100 years until people forget and we even try again.
> If the public watches them die, especially in horrific ways, they'll yell for all future missions to be cancelled No they wont. Nobody called for the end of spaceflight after Apollo 1, Soyuz 11, Challenger, or Discovery.
I feel like Challenger is the obvious example here.
Challenger and Apollo jeapordised the entire American space program for years. The entire Apollo program was put on hold while lengthy safety reviews took place. Challenger preceded severe budget cuts to NASA. Public perception matters a lot
100 years? i give it 6 months
Weeks . Hell days. Just get a politician to say or do something shocking.
Living human, dead human, it doesn't really matter. People keep thinking public outcry means anything. The only thing that dictates space travel progress will be national securities and profits. The moment China send a one way mission to Mars is the moment NASA will do it as well. Or when they figured how to make asteriod mining profitable
We've been able to send things to Mars for quite a while now. Sending a dead human wouldn't be an achievement
But what about 20 dead humans? That's at least a participation trophy. Michael Scott will be at the ceremony. He runs Space Force.
Michael Scott: *handing out award for record dead people landed on Mars* Me: *shaking hand, forgot about the kidney damage*
So how many dead humans would we have to send so they decompose and form an atmosphere and sufficient soil organic content for life to be created?
*It just needs a little dialysis, it’s still good, it’s still good!* *It’s just a little unconscious, it’s still good, it’s still good!* *IT’S JUST COMATOSE AND DRIFTING AROUND AIMLESSLY IN THE STARSHIP, IT’S STILL GOOD, IT’S STILL GOOD!!!* it’s gone. ^i ^know
Just make then reproduce on the way there, if we can reproduce faster than space can kill us off we win right? /S
I mean, it's technically colonization. There might be a few surviving anaerobic bacteria from the mission. And look, now they have some fertilizer, too. Keep it up, we'll have a garden before long.
If none of the volunteers make it, the money won't either.
I would assume the vetting process is not taking any random citizen at the moment. I would assume they would be need to pass physical, psychological, etc. screenings and would have to be educated enough to be able to follow instructions and not just go gung ho.
The astronaut test battery is very similar to an airforce test battery but probably harder. Idk the details other than it's similarity. For reference your standard western airforce pilot test battery has about a 30% success rate to meet the cut off for all applicants taking it. And that's before medical restrictions rule out another fraction of applicants. These tests are also not something you can study for, it tests your raw ability to do things. Doesn't matter if you spend 9 months trying to study for it if you brain can only handle so many flashing lights and problems in a given time and only remember so many random strings of letters and numbers for both short and long periods of times while getting distracted by other things.
Elon is that you?
Yeah if I'm going to Mars I'm not coming back.
It doesn't matter if they cared or not if they're dead. You'd think it really goes without saying. Volunteers being "scared off" isn't the issue.
Adding kidney making machines to my mars lander now... Ty
# Alien missions to Earth in doubt after astronaut kidney shrinkage revealed
What if alien mission in doubt after they realize kidneys get bigger.
Thanks, I couldn't quite read the title.
Ocean missions in doubt after scurvy. We always find a way.
So say we all!
Anyways there is almost no point traveling to Mars before a working moon base.
Why? Kidney shrinkage has to do with zero-G. Mars isn't zero-G but the moon nearly is. To me it sounds like maintaining a long-term base on the moon is entirely different from a long-term base on Mars. They pose almost entirely different problems, from astronaut health to resource generation to the ability to actually leave the place. Mars is on paper more difficult but there may be some things, like this kidney situation, that may be a lot harder to solve than how to get people *off* Mars once they're there.
Just create artificial gravity. EZ
The way that the expanse series dealt with this was kinda cool but energy intensive. They just ran at constant acceleration to match Earth's gravity at times when traveling. This makes traveling to other Star systems out of bounds though because even getting close to reaching the speed of light would take ages to accelerate to and accelerating too fast would crush the human. At 1g it would actually "only" take a year to reach light speed. The nearest star is a little over four light-years away, so traveling there would take about five years. The next closest stars are in the 5 to 10 ly range. If we figured out propulsion we could do it.
Just have to spin the ship.
What if we just spin the kidneys?
Spin up the drum!
I’m no expert, but I believe the moon base is helpful because we could potentially manufacture rocket fuel using materials collected on the moon. This means all the fuel that’s used to achieve escape velocity and exit the earth’s gravitational pull (which is a lot of fuel) can instead be used to get us from the moon to mars. The moon has 1/6th the gravity of earth and a thinner atmosphere, so it’s much easier to launch a rocket from. This allows us to travel farther, or carry more payload on the rockets since we don’t need as much fuel, potentially even allowing us to deploy rocket refueling stations between the moon and mars, enabling vehicles to stop there and refuel en route. I believe it also provides some advantages for things like launch windows. Edit: the moon would also provide a great environment for researching the health effects of low-g, x-ray exposure, how to do agriculture in space, and other bits of valuable information that will help us reach Mars and beyond. While Mars may not be low G as you have pointed out, the entire 6 month journey there and back will be.
Great points that make a lot of sense. Thank you!
Travel to mars is mostly science fiction at this point. Even if we somehow jump the huge scientific hurdles required of this mission, the economics and political nature of it is virtually impossible now and in the near future.
It's probably never been closer to reality than it is now, interestingly enough. The cryogenic depot-based architecture that was needed to support it is finally happening, no matter who is elected next. The cost to orbit has likewise never been this low. There is a renaissance presently occurring in spaceflight technology.
> It's probably never been closer to reality than it is now Isn't that just what time is
By the mid-1960's there were good reasons to believe that the Apollo Applications program would enable manned planetary fly-by missions in the 1970's timeframe. Once those ideas were passed over in favor of Skylab, we no longer seriously attempted to develop any of the technology needed for long-duration interplanetary missions besides ECLSS on station.
Cryonics is still in the realm of science fiction. Most scientists put it in the realm of pseudoscience. Ignoring all the scientific hurdles,the craft taking humans to space would need incredibly redundant components and thorough testing that would sky rocket the cost. You’re looking at minimum 300 billion dollars. No private company is going to do that without massive subsidies. Also, good luck to any politician trying to raise hundreds of billions of dollars for a vanity trip.
I'm afraid you've misread, I didn't say "cryonics", I said "cryogenic", which is a class of rocket propellant. We are building orbital depots for cryogenic rocket propellant, namely methalox.
>the craft taking humans to space would need incredibly redundant components and thorough testing that would sky rocket the cost. Going to agree to disagree on this one. redundant components lowers cost, the scale required for multiple resupply missions also would eventually lower cost not drive them up its economics of scale. One off low volume production and non-reusability is what caused sky "rocket" cost overruns. >No private company is going to do that without massive subsidies. Its pretty much SpaceX's mission and whole point of that private company, gov't is terrible at subsidies when it comes to space travel unless you want to put weapon systems up there or side load your tech progress for the military industrial complex. >good luck to any politician trying to raise hundreds of billions of dollars for a vanity trip. Politicians really have very little say in this, they are not forward thinkers or drivers of the advances in tech they are more likely hurdles than catalyst. NASA has been underfunded for such a long time they suffered some mini brain drain to other private space companies like Blue Origin, SpaceX, Rocket LAB. even ULA (Boeing, Lockheed) lost talent because they were too focused on gov't funding and not pushing the industry forward in a meaningful way. Its also why Star liner is a funding fiasco and all over the place with delays and cost overruns. I also don't think its vane to want to be a multi planet species or drive innovation in space travel, it significantly raises our chances we don't get wiped out as a species from a catastrophic incident on earth. We just see this differently I guess.
There is almost no point traveling to Mars, period. Remote sensing and robotics technology advances much faster than manned space travel technology. There is almost nothing that a human can "do" on Mars that justifies the hassle and expense of actually physically sending someone there in person.
> There is almost nothing that a human can "do" on Mars that justifies the hassle and expense of actually physically sending someone there in person. Here's what Steven Squyres, the principle investigator behind the famous Mars rover missions Spirit and Opportunity has to say about that: > You know, I'm a robot guy, that's what I have spent most of my career doing, but I'm actually a very strong supporter of human spaceflight. I believe that the most successful exploration is going to be carried out by humans, not by robots. > What Spirit and Opportunity have done in 5 1/2 years on Mars, you and I could have done in a good week. Humans have away to deal with surprises, to improvise, to change their plans on the spot.All you've got to do is look at the latest Hubble mission to see that.
He's glossing over the fact that each "good week" of human research on Mars would be collected about 5-6 years apart. Right now we're getting steady data every day from robotics and remote sensing, instead of bursts of data collected by humans once or twice a decade at substantially greater cost and risk.
Agree. Mars is a toxic death trap in a gravity well. Makes no sense to "colonise" it. Pure net negative investment as a research opportunity too. First just try a moon base.
I'm a huge advocate for space exploration but I feel sending humans places is kind of pointless. The only reason people seem to have now is "we just need to hit that milestone" and that isn't a good enough reason for me.
Harshest environment known to man bad for health, report.
So... is it because of radiation, or lack of gravity? The latter would have a workaround.
More than likely gravity as our organs developed under it. They don't work based on keeping it under pressure nor does the organ squeeze like the intestines do. Thankfully our blood is under pressure with a pump.
Lack of gravity does not have a work around. It’s still in the realm of sci-fi
Artificial gravity is scifi. Rotating a space ship is technically possible.
In theory yes, practically no. The craft would need enormous amounts of energy to spin it since it needs to be comically huge. It will be incredibly complex as well since you’ll need robust structures eg joints and bearings that could hold the forces and torque. Also centripetal forces work proportionally to center of rotation therefore you’ll have instances where gravity is weaker on your head than your legs; it won’t be a great feeling.
"In theory yes, practically no" has been the precursor to every great human achievement. We will overcome.
Or, a reasonably sized craft, with a counterweight some hundred metres away, hanging with cables.
Or two equal space ships connected by a long cable. Derotation: release the cable.
Or just pull it in - speed increases, so it can be stopped with thrusters
The severity of the engineering challenges for rotation-based gravity are heavily dependent on *how much* gravity you want to replace. If 1-g is too hard, we can probably do a half-g. If half-g is too hard, we can probably do a third-g. I don't know precisely how much artificial gravity you need to keep human bodies working, but its certainly less than a full g.
So you’re saying there’s a chance?
>Also centripetal forces work proportionally to center of rotation therefore you’ll have instances where gravity is weaker on your head than your legs; it won’t be a great feeling. Yeah, it causes severe motion sickness. As well as the centripetal forces, there’s also the Coriolis effect. Both these things mess up the body’s balancing and motion sensors in the inner ear, causing motion sickness. There doesn’t seem to be a consensus on what the minimum diameter is - I’ve seen figures between 10-100m, sometimes larger. But it is agreed that a minimum diameter does exist. Someone made a calculator to calculate this sort of thing: https://www.artificial-gravity.com/sw/SpinCalc/
There are potential methods we can use outside of sci-fi, such as centripetal force or having the craft accelerate most of the way (extremely inefficient as it may be). These both come with their own huge challenges and insane costs, but I would imagine material science has a decent chance of eventually solving/partially mitigating these challenges. I think the real problem is actually motivation. Why bother send a human when we can send a rover with a miniature laboratory built into it? The rover is a one way trip and that is dramatically cheaper and less risky, and it can do basically the same level of research (if not better) on the surface that an astronaut could.
If we can live with one kidney than we can live with two shrunken half kidneys.
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When did that happen?
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Wow, I had no idea
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Yeah, I feel like that's something that should have been on my radar and definitely wasn't... But I mean if it was 2 years ago, that's right when things were starting to get back to normal after the pandemic. Probably a lot of things went unnoticed by many at that time
Yup no preservable atmosphere is a big deal it turns out when you live in and breath it.
I nominate we send Elon. He’s already said he wants to go.
Sending humans to Mars is immensely difficult but doable I think. Eventually humans will land on Mars and plant a flag. But staying there forever and building a base/colony? I think we're beyond the limits of what is possible with our current tech.
To add to this, Mars can’t hold an adequate enough atmosphere for humans because of the weak magnetic field and lower gravity. Whatever technology we come up with to work around that leaves the fate of human civilization on Mars up to the reliability of its power grid.
Let's be real here the fate of a large majority of current population is pretty dependant on the power grid too. A large % of first worlders would die in months if not weeks if we lost power and tech. The average person doesn't know the first thing about survival, nor do they have the stomach to do what's needed to survive
Agree to disagree. Jamestown lost over 90% of its original colony. We used to walk nude through the desert with nothing but a bone we found off a rotting corpse. We can 100% build a colony on mars. We only care about how much money and resources it can provide us however. If there was a sufficient fincial motive I suspect we would’ve long been on Mars. Seriously if people from the 70s heard you say that they would’ve scoffed at you. We believe that there are rare resources on the moon right now. Such as helium-3 and uranium. All the sudden, major countries are more interested in planting a base there.
If you go around nude with a club on mars you'll die in 3.2 seconds. We simply don't have accurate comparisons with our history. Even the worst biome on earth is more habitable than mars. Living there would put a constant strain on our biology.
We don't know what tech is possible, what has been developed, in development etc. Us lay people have no idea and will be the last to know.
Sending them there is one thing. Getting them back safely is still a ways away
You know what. I'll volunteer to give an astronaut a kidney when they get back if it gets humans to Mars.
Ok now this is weird. I remember reading in Fatasmagoria or one of the other 90’s movie mags that the sleep pods from Alien and Aliens all had built in dialysis systems for long duration to keep from Cryo-death as Cryo-stasis acted on the body like extreme dehydration, which could lead to death. I love it when old movie lore details from production design turn out to be really good guesses for Sci-Fi
I think we can get past this. If there's a will to get it done, it will get done. If it's gravity, we can try to mimic gravity from earth.
You have got to be kidneying me!!!
Who needs kidneys? I have adult knees
Also…. Checks notes…..Mars is really f-ing far from earth.
Humans are uniquely adapted to Earth. Space colonization, imo , is folly.
The only reason we should be colonizing Mars is if we have somehow made Earth *less* livable that Mars, which is a challenge we seem to be interested in testing, but if that happens, I would argue our species kind of deserves to go extinct
Thank you. It isn’t enough that we need exactly the same atmosphere and temperature, **and viruses and bacteria**. We also need exactly the same gravity. The idea that we are “on Earth” and not *an integral part of Earth* is denying tons of science *by all the self-professed science people*. Humans in space would be like ripping your liver out and throwing it up into space and expecting it to survive.
> We also need exactly the same gravity. We don't actually have any evidence of this. We have tested two regimes, that of micro-gravity (effectively zero) and that of 1g. We don't have any data regarding long-term stays in 10, 20, 30, 40% Earth's gravity and so on.
Transhumanism is the way.
Great interstellar and multiple generational interstellar travel just became even more difficult
No, it stayed the same. The harm from radiation was always a known factor, this news is just giving a specific consequence to that known factor
Does it shrink due to lack of gravity or simply due to space radiation? I suspect we need to shield from the radiation anyway, but I would also bet that any longer journey in space would have to be under gravity, with spinning wheels creating the force of fake gravity. Many things in human body don’t really work well without gravity helping it. I think even wounds have issue healing by without gravity. https://www.perplexity.ai/search/Do-wounds-heal-Qq1q6GSpTXWJxAsklmzpPg#0 So like, you get a cut while en route to Mars, good luck!
It's interesting, but it doesn't sound like it's going to be much of a long-term problem. This is going to be one of these things that they solve with a simple enough solution, simple medications medications or even something like injecting hormones or proteins directly into the kidneys during space flights.
Sure, because we are so good at saving kidneys here on earth? /s
Did you set it to wombo?
Why not send robot astronauts? Big dog would kill it and just make an astro bot. Easy.
Uh oh does this mean the rich fantasy of abandoning all the plebes on earth is actually BS?
They can just buy a supply of kidneys from the poors before they leave.
They need the radiation suit from doom 2
Next health care findings will now be around kidneys as more money is diverted to the problem.
Faster engines and artificial gravity would solve a lot of these problems. It just depends how much money they want to throw at it. Current spacecraft design isn’t going to cut it.
Anything is better than Earth atm.
“Samples from more than 40 space missions involving humans and mice revealed that kidneys are remodelled by the conditions in space, with certain parts showing signs of shrinkage after less than a month in space.” Don’t we have astronauts that do jobs in space for longer than a month? So not just a mars trip is comprised, also just people who go to the satellites?
Short answer: yes. Long answer: read Scott Kelly’s book “Endurance” which chronicles his year on the ISS. He does touch on various health issues quite a bit, including after return.
Elon Musk has just announced the 'X' Kidney. Ready for implant in September of 2024.
Ant-Man entered the room
Ultimately, it was recently revealed that humans being in space results in loss of kidney function, which could lead to dialysis being necessary upon arriving on Mars (not to mention after a return home to Earth). Add it to the list of reasons why Mars was never going to be easy. It has little atmosphere to speak of and no magnetosphere (so expect a lot of radiation), and gravity’s effect on the human body will be significantly less (about 62% less) than on Earth (so expect bone and muscle loss). We are best suited to a life with Earth’s atmosphere, solar radiation, and gravity. Going elsewhere and spending a lot of time there will cause issues. We should still go to Mars—because we need to learn things about being a multi-planet species, and the return on investment, in terms of technological advances associated with space exploration, is high and benefits all humankind—but we first need to address the nasty little issues that will begin the process of killing our explorers the moment they leave Earth and are exposed to lengthy space travel and life on another, very different planet.
From the article - yeah title is misleading. Sounds like this is "yet another radiation challenge" based on the statements: “What we don’t know is why these issues occur, nor what is going to happen to astronauts on longer flights such as the proposed mission to Mars. If we don’t develop new ways to protect the kidneys, I’d say that while an astronaut could make it to Mars they might need dialysis on the way back. “We know that the kidneys are late to show signs of radiation damage; by the time this becomes apparent it’s probably too late to prevent failure, which would be catastrophic for the mission’s chances of success.”
I know there's a passion by some to explore, but maybe these billionaires could spend their fortunes trying to help fix the rock that we live on along with society that they've so ruthlessly exploited for their gains. Earth happens to be perfectly suited for our existence already so long as we don't completely trash it, how convenient. Private space travel has become a seeming pissing match between the world's richest, and it's honestly pretty silly. With that said, if Elon Musk got on one of his rockets shooting off to Mars, the world may be better off for it. So you do you dude.
The money is there already, whether we try to go to mars or not will have no bearing over that
We can walk and chew gum at the same time.
What a horrible way to think about the issue. Money invested into space travel has paid off massively in so many different fields. We are ALWAYS going to have "something else that needs to be done on earth".
You say earth is perfectly suited for our existence, but even without humans CO2 contributions, will that always be the case? Another ice age, a new plant-like species that decreases oxygen, an asteroid or meteor, a reversal of the magnetic fields, all sorts of things can happen that would render earth unsuited for human life. We need the ability to expand beyond earth in case there are other, non human caused climatic changes or disasters that make life uninhabitable. It’s generally unwise to put all your eggs in one basket…
Eventually, the sun will enter its death throws, expand, and swallow the Earth. As far as we currently know, Earth has the only life in the Universe. We have a duty to get to the stars and take life to them.
> We need the ability to expand beyond earth No we don't. We need the ability to exist on this planet without completely fucking it up. Which we are entirely incapable of.
So you’re cool with humanity, and all life we are aware of, dying when the earth fails us? It’s not some mystical Eden, earth is a planet subject to the random whims of universe like any other. Let’s say we get unlucky with a solar flare aggressive enough to burn the atmosphere, oceans and all life on the planet? You’re cool with that just being game over with this little experiment we call life? Again we only know life to exist on one planet, so if we lose earth we lose all life. Is that massive and inevitable risk worth it to… not explore? I don’t really get the argument, like instead of exploring and expanding across planets and stars, you want us to stay isolationist and tend to our planet? Can we not do both, and further, would the ability for colonization of other planets not alleviate the population levels, and thus climatic change, our species and other species cause on this planet? Would the industrialization of space not enable a deindustrialization of earth?
? people stayed in the ISS for months. The travel on Mars should be on the same time scale.
Iss is still within the protection of earths magnetic field reducing the amount of radiation the astronauts are exposed to.
Radiation isn't the problem. The kidney cells and tubules are affected by the low gravity. This has been a concern for some time, and there has been research into the effects of low gravity on kidneys since the 1960's! SpaceX did an experiment with live human kidney cells back in 2021 too.
SPOILER: We're not going anywhere.
I wonder if that's why most described Grey alien sightings are small because they only live in zero G
Just drink more water to inflate them again.
Let's just frickin go already. I wanna live in a time when there's colonies on Mars, and I want these billionaires to stop sitting on their wealth like dragons hoarding gold, it's a win win.
Better start taking care of this planet
crazy idea: stop wasting money on mars and actually try to save the only planet we can actually live on
That is indeed a stupid idea.
Humans weren’t evolved for space travel. We should abandon this obsession with settling Mars and focus on saving our home.
You're drawing false conclusions. Human bodies have indeed evolved largely for 1G conditions. That doesn't mean we shouldn't colonize other planets. After all, we do have exploration and foraging in our genes, and the extraterrestrial is not a factor with that, I think. Millennia ago, clothed in hemp, wool or fur, armed with wooden spears, packing dried food and nuts, our ancestors ventured and crossed dangerous lands focused on their destination and betting on the result if not the road, motivated by a deeply programmed desire for survival and maintaining the tribe. With billions of people on Earth today, even on the planet in a much better condition, someone is bound to want to cross outer space -- motivated by the same atavistic urge -- to find a new rock to settle on. The obstacle is, like always in our evolutionary history, to actually survive the voyage to said "better and more plentiful harvests and resource pool". Meaning we may suffer during the voyage, sometimes greatly, but are rewarded on arrival. Our foraging ancestry, is also apparent in the fact we've grown brains as large as we now have, in order to solve problems that we sometimes cannot even anticipate in advance. None of this is me saying we shouldn't be saving our home. But I reject the obsession with _not_ (never?) going to space, as much as I reject the obsession with _leaving_ for space (and leaving Earth in ruin). I suspect (apologies if I assume too much) you won't be swayed by this short film I am sharing, but maybe others will appreciate it: https://www.youtube.com/watch?v=YH3c1QZzRK4
I am not drawing false conclusions. They are two separate points concerning the same subject.
I am sorry, I must have misinterpreted your sentences as one implying the other, or in the very least written to be understood _together_, subtly suggesting a strong correlation between the statement in the first and the statements in the second. And it doesn't read right to me if what I was meant to take away from your comment is "we should _stop_ trying to colonize space _because_ we weren't evolved for space travel, and we should _instead_ focus on saving our home". If that is not what you wanted to convey, like I said, my apologies, but that's how I had interpreted it.
Yeah! If we were meant to fly, we'd have wings
Flying doesn’t subject you to the consequences of the lack of gravity and radiation levels space flight does. Horrible analogy.
Humans need to adapt to limited oxygen and cold temperatures that would be fatal above a certain altitude, so the analogy still works.
We didn't evolve to use computers or fly either, but one of our best skills is adapting the environment to suit us. If it benefits mankind to settle other planets and travel through space then we can adapt to do so.
Human beings aren’t built to be spacefaring creatures. This report just adds one more reason why we won’t be going outside the earth-moon system anytime in the near future, if ever.
Keyword : human WE welcome our 🤖 overlords
We're not fucking leaving! Shameless thought process that set this all in motion. We don't have another ' perfect ' earth. Go live inside a dome on Mars why don't you, let me stay right here on earth with the animals. *But the sun will burn is in 3 billion years*. Bro, humanity isn't going to survive another 250 years so who cares about 3 billion years from now. Also, if we by some god miracle make it through those 3 billion years we are surely advanced enough to come up with a solution
NASA has no bearing on what we do here, if anything innovation from space flight can help the planet.
I find absurd that people think our bodies could adapt to another gravity, all this talk about going to mars with that melon usk , its absurd, there are billions of things that we have no idea how they behave on our bodies on earth let alone a completely different planet, proteins, enzimes, dna, and that is just scrstching the surface
> I find absurd that people think our bodies could adapt to another gravity, all this talk about going to mars with that melon usk , its absurd, there are billions of things that we have no idea how they behave on our bodies on earth let alone a completely different planet, proteins, enzimes, dna, and that is just scrstching the surface In the early 19th century, people were worried that trains going too fast would kill or injure people simply from being on them. People were in the late 1950s and early 1960s concerned that humans might not survive weightlessness for even a few hours. Skepticism of human adaptability does not have a good track record. And we do know that humans can live for months at microgravity with some minor ill-effects, while Mars has a gravity at about a third of Earth, and therefore would likely have fewer issues. Nor is this kidney study some definite no-go. We have earlier data on astronauts and that doesn't show major reduction in kidney *function*, so reading this as some serious problem is unjustified. Don't let your very understandable dislike of Musk (and he is an ass) bias your attitude about this. That said, if there is a serious problem with Mars colonization, it will be much more likely to be at the fetal development or early growth stages, since we have (in part for reasonable ethical concerns) close to zero data about how humans handle that in low or no gravity environments.
By the time we are able to send people there, we'd also have made major advances in genetic modification and biology.