I just ran across this article, which is a side of 'space travel' we don't hear about too often. It shows quite clearly that while we can live in a weightless state, if we stay there too long our bodies can't readjust to gravity again. Kinda scary stuff. Good to take into consideration if you're a hard sci-fi writer who deals in space travel and/or living. https://www.ranker.com/list/health-problems-from-a-year-in-space/mick-jacobs?utm_content=inf_10_3514_2&utm_source=facebook&utm_medium=pd_inf&utm_campaign=SE&tse_id=INF_f75d2690d15211e7b926579f881108d6
There's a reason we haven't heard so much as a peep from the far reaches of the cosmos. Charles Stross, well known writer of epic SF/F has an essay that spells it out rather coldly, that we are in fact not destine to travel among the stars. Humankind will never set foot on a world beyond our tiny solar system. The article, The High Frontier, Redux must be quite sobering to the dreamers among us. http://www.antipope.org/charlie/blog-static/2007/06/the_high_frontier_redux.html
I hate to keep going on about this book, but Existence by David Brin does an excellent job of overcoming the Fermi paradox, and also deals with it in a way which mitigates most issues with interstellar travel.
Interesting article. I'd heard about the experiment with Kelly and his twin, but didn't know he was back. It seems that most of the issues (skin rashes, bloating, atrophy, joint degradation) are related to the return to gravity. So I would be interested to know what would happen if an animal stayed in zero- (or low-) g permanently. We could probably create a vessel with sufficient radiation shielding to travel long distances, and I would have thought that staying inside that environment with no gravity would be fine, but of course gravity could become a problem when we reached our destination.
Interstellar travel isn't like tossing horseshoes. You don't get points for being close. You either solve all the problems that come with humans traversing light years of space, or you stay at home.
Gravity is just an accelerating force, in fact, if you study the maths of general relativity, it vanishes entirely. This means that any acceleration can mimic the effects of gravity. Engineers plan to do this by spinning their spacecraft. This both stabilizes it and can easily produce an acceleration of 9.8m/s/s along its edge, so microgravity does not appear to be something we can’t work around. Our current limitation is that we don’t know how to shield ourselves from cosmic rays.
I only say “most issues” because it Spoiler: Spoilers for ‘Existence’ doesn't involve biological organisms physically travelling across interstellar distances. They are converted to sentient digital life-forms which are then propelled into space inside artificial environments. It means human consciousness can cross interstellar space without the inconvenience of keeping a physical body alive in space.
No. in fact, almost every object that we've sent out into deep space we spin up because the gyroscopic forces keep it stable and resist it being pushed off course by things like radiation pressure. The necessary velocities to produce Earth-like gravity angular acceleration is actually fairly small, an object about a quarter mile in diameter would only have to rotate maybe once a minute. It'd take power to get it up to speed (but not much) and once up to speed, the ideal required energy to keep it going is zero. You'd only have to overcome whatever friction you have.
The Space Between Us uses the theme of the effects of gravity and not being able to return to Earth. It's about a boy born on Mars who has serious heart problems when he comes to Earth as a teenager. Good movie.
It'd take a whole load of cash to get it up there presently—beyond the budget of some of the bigger nations (I've been you-tubely informed)—it's all to do with getting a decent 1 G analog. Smaller stations that spin would have a noticeable differential between head and feet and that's apparently v. disorienting. So big engineering project + much material is just beyond our means (and inclination at the mo). Bring on the 'space elevator' and we'll be there.
This isn't entirely on topic, but this thread reminded me and I thought people interested in this thread might also like to know. I've just watched a mini-series on Netflix called Mars. It's half real-life documentary about present-day attempts to mount a manned mission to Mars, and also Elon Musk's plans to populate Mars, and half fictional drama about a team of astronauts who actually do it. I found it interesting to learn about what is being done today, and also to see a dramatisation of what could happen in the future.
Most engineers in the field that I know do not expect to send materials up to space for a big project like that, Earths gravity well is just too strong. Well most likely end up using our Moon as an easy launch-off point for big projects. The delta between your head and feet would not cause much problems. The problems result in when you turn, the gyroscopic forces will feel very strange.
I remember the book of 2001 had a scene with someone who had been born and raised in zero-gravity. She was something like six feet tall at about twelve years old, and found the idea of "falling" to be strange and disturbing. No idea how accurate that is, but it's an image that's stuck with me.
Yeah, I'd read about that. What I find startling (and scary) is that this man only spent a year in zero gravity, and it sounds as if his body is basically falling apart. There would definitely need to be foolproof gravity machines on any floating spacecraft, including space stations, if they are to be viable—assuming the people on them would plan to return to earth or another planet at some stage. Mind you, this inability to ever return to a planet after being in zero gravity for a while might be a basis for a good story.
That's fascinating. I hadn't thought about the psychological effects of only every having existed in zero-g. Not having a concept of 'falling' is an obvious effect now you mention it, and I imagine the idea of it would be terrifying if you had never experienced it. The idea of being pulled suddenly downwards without being in control of this would be horrific if you have only ever known weightlessness.
Well technically you could travel the galaxy. You would need to use a radiation barrier, like an outer hull filled with hydrogen, water, or some other element/molecule that does not weigh too much, but does inhibit radiation from getting into the ship/environment. If your concept culture is technologically advanced enough they could in theory build a habitat using planet materials to build a large spinning cylinder habitat. It would be able to be propelled forward by a fusion engine, and your habitat could be self sustainable if they know what they are doing. Though this would be like rolling a few dozen neighborhoods into a cylinder with a few spots cut out for solar litghitng, and would be a multi-generational type (or colony ship if you will). But if you were to live in a zero-G environment, then you would lose bone density and muscle mass. That is why they have things like centripetal spin to simulate gravity. As well as things like strapping some one down to a treadmill to try and stave off the effects of ZG. Granted this would apply similarly to low grav bodies as well (moons and smaller planets). Though with planets like Venus that have a 91% the grav of earth might not be as bad as say the grav on Mars which is 70% that of Earths. Though I think you could counteract/compensate for the lower gravity by adding weight to the people (similar to deep sea divers), to make up the difference for the lack of gravity. (Though this would not work so well on the moon for a comparison). While it has been mentioned to download your consciousness into a machine, and travel that way. But would it not make more sense to try and directly integrate the physical brain (and the eyes along with a few other things to keep the brain 'alive' inside the machine), would in theory be the best solution to travel for an extremely long period of time in a ZG environment, with minimal to no effects on the being. And yes this would still be considered a 'living' being, due to it being the very core biological part of the person (which really is our brain). That would be the most ideal option for 'real' beings traversing space, and not just some fancy AI, and can actually exp. the whole ordeal.
Interesting idea. This also kind of happened in Existence when Spoiler: Spoilers for Existence a character was blown up and most of her body destroyed, and her brain was transplanted into a robotic body. The problem with this approach is that the brain would still need nutrients, oxygen and waste disposal, all of which are difficult to maintain in space. Much better to replicate the brain in purely digital form. I hope this is the future of human life anyway. Download us all into a computer, let the biological humans die off, and allow the rest of the planet to function as it is supposed to without us interfering with it.
No, you would not be considered a, "human being". You cannot digitize human consciousness nor replicate the human mind in any form other than the organic muck it exists in.
How do you know that? The required technology doesn't exist right now, but there's no reason to believe that a sufficiently complex machine couldn't result in a conscious mind.
Very wrong. The human brain is a chemical machine. Chemical processes strictly follow mathematical laws, which are deterministic. A computer, given enough power, can simulate any physical process.
I am in no doubt that inorganic life forms will exist at some point in the future. I hope this will be within my lifetime. The only question in my mind is whether these life forms will be considered human. Clearly they are not Homo sapiens. I suspect also that at least initially they will be limited in cognitive function in order that they can be created and destroyed without moral objections from most people. But if you extend the concept of humanity to encompass human traits of intelligence, sapience, empathy, emotion etc., then I see no reason why the term "human" could not be broadened to include inorganic life. The subject of emotion is an interesting one when considering inorganic life forms. Most emotions are fundamentally based on physical bodily sensations (especially the more base emotions like fear, rage, lust) and even the more complex ones often contain elements of this (embarrassment, shame, amusement). So how an inorganic life-form would experience emotion I don't know. Without a physical body to react to the environment, I question whether an inorganic life-form could truly experience emotion. And without experience of emotion you can't have empathy, and without empathy you are in trouble when it comes to interacting with other life-forms. So unless artificial life-forms were programmed to simulate emotions and empathy, there could be problems interfacing with them. And programming a conscious mind to behave in particular ways is ethically dubious to say the least.
Emotions are all emergent properties. of the chemistry, which is deterministic. AI will absolutely not be programmed. Even today's AI is not programmed, they're neural networks and we're not entirely sure how they work most of the time.
Exactly - inorganic life-forms will not be chemical in nature, so there will, I assume, be something fundamentally different about their experience of consciousness. They can be given potential for language of course so that they can communicate with organic (or other inorganic) life, but whether they will experience emotion as we know it, or even at all, I'm really not sure. Without a biological body full of chemicals, it's hard to imagine what an emotion would feel like. This was what I always hated about Data's character in Star Trek. He reacted to emotions as though he were an organic life form, which just didn't seem right. The imperatives for emotion in an inorganic life form will be completely different. Fight/flight/freeze won't exist for a start, and most emotions we know of are basically build on top of those. Understood, but presumably they will have to have some programming of functions to make sure they do what we need them to do, and don't do things we don't want them to. Especially if they achieve consciousness, I assume they will be programmed with some constraints, failsafes, and mechanisms to control them. Even if 'programming' means laying down gross structures for the neural networking and interfacing with the physical world before letting things take their course in terms of the AI learning independently.
