Will human extraterrestrials be able to visit earth?

If a human is born and raised on the Moon or Mars or other of the planets that could possibly be inhabited, they will not experience the constant force of earth's gravity.

So, they won't have the same developmental requirements that humans on earth do.

When Apollo astronauts returned, they could barely walk even after experiencing such a short time in space as adults.

So, would a human extraterrestrial be able to visit earth and walk around in our gravity with organs and muscles capable of the various loads they would experience?

 

That's a very interesting question. I think that humans would have to be genetically altered for a specific planet before we go into those kinds of difficulties. I would assume humans can adapt to whatever planet they visit. It would just take a little time.

 

Short answer: not immediately. There would be an adjustment period. It's possible someone planning a trip to Earth could do a lot of exercise during the 18-month trip, so by the time they arrive they're somewhat prepared.

Semi-sci-fi answer: exoskeletons. There would still likely be issues with how well your organs coped with the much-higher gravity, but again that might be something you gradually adjust to on the journey.

Maybe it becomes a thing for rich Martians to visit Earth every decade or so. First, it's an exotic vacation. Second, when you return home, you're a physical superman. I could see sports leagues being entirely populated by players recently returned from Earth, with teams routinely sending their players to Earth for high-gravity training.

 

Interesting!

I'm not so sure that a lot of exercise would do the trick. I suspect our bodies grow the way they do in part due to our environment. So for example a baby may no longer grow a strong spine in the relative absence of gravity. That might not be fixable by exercise. Spinning cribs? Yikes!

Exoskeletons!

 

True about how bodies will grow in lower grav. But “lower grav” isn’t “zero grav”. Our skeletal growth will still be guided by gravity, and our bones will still be relatively strong.

Mars gravity is 38% that of Earth. So imagine a 150-pound person suddenly weighing 395 pounds. Difficult? Yes. But doable.

Let’s say that during transit, they live in a spinning wheel to simulate gravity. Over the course of the 18-month trip, you gradually increase the gravity to Earth normal. That would be 0.11% of the difference each day. By the time you arrived you might be close to used to it.

 

How would humans adapt? How much time is "a little time"?

Minor evolutionary changes take thousands of years, and major changes take more like tens of thousands, hundreds of thousands, or even millions of years.

There isn't a single place that we know of in the universe that wouldn't kill a human dead within seconds of unprotected exposure to the environment.

The only way humans are currently capable of surviving off Earth are by artificial means which create an Earth-like environment.

 

Good point about Mars still being a significant percent of earth gravity.

I'll bet there is some data on this somewhere.

Surely we've grown some mice on the ISS. Having mice born into and developing in zero gravity might give some clues.

 

Since Mars has lower gravity than Earth, humans can survive there. Humans can always survive less than 1G of gravity, assuming they exercise. It's only a heavier gravity of a planet other than Earth that could kill us. Or so I hear.

The atmosphere is its own issue. Now there's a trait that would have to be its own issue and genetic engineering project.

 

Yes - going to a lower gravity location isn't likely to be a problem, though there would probably be difficulties doing some tasks where gravity helps.

The issues of trying to stay alive on the Moon or Mars due to environmental factors is a more serious and nearer term problem, I think. Even with a heated space suit and breathing apparatus there is a definite limit to how long a human can stay alive on the Moon's surface due to radiation. I wonder how much time a worker would have for building adequate radiation protection. How much "surface time" would be allowed before it's time to get the worker back to Earth?

 

If humans go into space long term, we will need to take or make our environment as we go, coming back to earth should be relatively easy. If we are stupid enough to build colonies on planets or moons that is a different story.

 

We don't know if the 1/3 gravity of Mars compared to Earth, will affect astronauts like zero gravity, or to what extent if it does. But the effects of low gravity are known to be severe.

https://en.m.wikipedia.org/wiki/Weightlessness#Human_health_effects

If a person adapted to the Martian environment, they would likely not be able to function on earth for long; at least not without a very long period of adaptation. But a baby may not even develop the same on Mars, as on earth, They may well be as out of place here, as much as we are in weightlessness.

Consider for example an underdeveloped immune system. A trip to Earth might mean certain death by infection.

 

Surviving on Mars is different from living there long term or colonizing it. We've no idea if a healthy baby could be carried to term, and grow up healthy, in a Martian gravity. It may just be impossible.

 

What if Earth humans visit another planet where the surface gravity is three times as strong?

 

Probably any planet where intelligent life originated will not have gravity all that much lower than Earth. If the gravity were much lower there would barely be an atmosphere and not enough pressure for water to exist on the surface.

If the gravity were maybe only 50% higher on Earth than the planet they came from, they would probably be able to adapt.

 

Mars is only 1/3 Earth gravity, but the loss of the atmosphere is due to solar winds, in turn because there is no magnetic field to protect the planet.

https://en.m.wikipedia.org/wiki/Atmosphere_of_Mars

 

Whether it is ET's visiting Earth or humans visiting other planets, seems like it's not just gravity that can create some issues, but what about things like air composition, food, amount of light, magnetic field, time, indigenous diseases/viruses/bacteria, etc.?

 

Synthetic gravity.

 

There is no such a thing.

You can create your own gravity as on carnival rides - force due to rotation.

 

The optimal frequency of a humans magnetic field is exactly the same as that of the earths. Our frequency can become imbalanced causing headache, anxiety other problems. It can be 'reset' by any means that prolonguedly puts you in contact with the earth, like standing in a creek, holding on to a metal pole imbedded into the earth, or just walking barefoot for a while. Doing this is commonly referred to as 'grounding.'

I would imagine other planets have substantially different frequencies that could cause a permanant imbalance that could lead to problems with human habitation.

 

This is not science. It is pure speculation at best. Strictly speaking, it is pure crackpottery.

I strongly suspect that the Schumann frequencies are what originally drove our brainwave frequency. But I am talking about things going back to the primordial soup or sludge. And I certainly wouldn't declare it as fact. It is just a very tempting line of reasoning that makes sense.

 

Perhaps. Perhaps not.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3265077/#sec1title

In any case, spending time outside connecting with nature never hurt anyone, so if its 'crackpottery', its harmless crackpottery.

 

There is also the problem of the Immune System.
Common microbes baby's immune system learns to disregard
may be immune challenging to extraterrestrial born.
And microbes the immune system should reject may . . .

Will they take probiotics to colonized worlds


Moi

Across an immense, unguarded, ethereal border, Canadians, cool and unsympathetic,
regard our America with envious eyes and slowly and surely draw their plans against us. ​

 

Try going to an overseas nation unvaccinated and then tell us all that again....if you can.

 

As I understand it, Mars isn't habitable for humans? I thought you'd know that, Will??

 

@tecoyah


There is also the problem of a baby's immune system learning
what NOT to get reactive over.
That ability is unique to baby.

GET IT OR NOT!