Spacecraft Designed That Could Carry 2,400 People on a 400-Year Trip to Alpha Centauri (livescience.com)
- Reference: 0178626334
- News link: https://science.slashdot.org/story/25/08/09/1731242/spacecraft-designed-that-could-carry-2400-people-on-a-400-year-trip-to-alpha-centauri
- Source link: https://www.livescience.com/space/space-exploration/proposed-spacecraft-could-carry-up-to-2-400-people-on-a-one-way-trip-to-the-nearest-star-system-alpha-centauri
> The craft, called Chrysalis, could make the 25 trillion mile (40 trillion kilometer) journey in around 400 years, the engineers say in [2]their project brief , meaning many of its potential passengers would only know life on the craft. Chrysalis is designed to house several generations of people until it enters the star system, where it could shuttle them to the surface of the planet [3]Proxima Centuri b — an Earth-size exoplanet that is thought to be potentially habitable.
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> The project won first place in the [4]Project Hyperion Design Competition , a challenge that requires teams to design hypothetical multigenerational ships for interstellar travel.
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> Before boarding the ship, the Chrysalis project would require initial generations of ship inhabitants to live in and adapt to an isolated environment in Antarctica for 70 to 80 years to ensure psychological wellbeing. The ship could theoretically be constructed in 20 to 25 years and [5]retains gravity through constant rotation . The vessel, which would measure 36 miles (58 km) in length, would be constructed like a Russian nesting doll, with several layers encompassing each other around a central core. The layers include communal spaces, farms, gardens, homes, warehouses and other shared facilities, each powered by nuclear fusion reactors....
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> This plan is purely hypothetical, as some of the required technology, like commercial nuclear fusion reactors, don't yet exist.
Thanks to long-time Slashdot reader [6]fahrbot-bot for submitting the article — and for sharing this observation...
"My first thought was that someone read Arthur C. Clarke's book, [7]Rendezvous with Rama and used it as a model design!"
[1] https://www.livescience.com/space/space-exploration/proposed-spacecraft-could-carry-up-to-2-400-people-on-a-one-way-trip-to-the-nearest-star-system-alpha-centauri
[2] https://www.canva.com/design/DAGmr3ubC8E/LHHAeeAIGGQe_TkZVs-PXA/view?utm_content=DAGmr3ubC8E&utm_campaign=designshare&utm_medium=affiliate&utm_source=Future%20PLC._221109&utlId=hcfa85973cc&clickId=S1J3jSylzxycUPjR9Tw2iW5PUkpxfX1uFUVjwI0&irgwc=1#1
[3] https://www.livescience.com/63546-proxima-b-nearest-exoplanet-habitable.html
[4] https://www.projecthyperion.org/
[5] https://www.livescience.com/52488-centrifugal-centripetal-forces.html
[6] https://www.slashdot.org/~fahrbot-bot
[7] https://en.wikipedia.org/wiki/Rendezvous_with_Rama
Question (Score:2)
where it could shuttle them to the surface of the planet Proxima Centuri b — an Earth-size exoplanet that is thought to be potentially habitable.
What do they do if they get to his planet and find out it can't support their life? Do they stay in the system and live their lives in the ship? Do they turn around and return home? Go some place else?
This is all well and good to talk about sending people to a planet, but thinking it's habitable is far different from knowing it's habitable.
Re: (Score:3)
> I would think a 400 year trip is way to long what happens 200 year later when the next bigger faster ship passes them on a 40 year trip.
What happens when the first generation of kids comes of age, notices they never gave consent to be confined to a ship for their entire lives, and decides to turn around? And about that 40 year trip. Bear in mind this math is for a 2000 kg ship, 1 billionth the size of the proposed one:
https://www.antipope.org/charlie/blog-static/2007/06/the_high_frontier_redux.html
> Now, let's say we want to deliver our canned monkey to Proxima Centauri within its own lifetime. We're sending them on a one-way trip, so a 42 year flight time isn't unreasonable. (Their job is to supervise the machinery as it unpacks itself and begins to brew up a bunch of new colonists using an artificial uterus. Okay?) This means they need to achieve a mean cruise speed of 10% of the speed of light. They then need to decelerate at the other end. At 10% of c relativistic effects are minor — there's going to be time dilation, but it'll be on the order of hours or days over the duration of the 42-year voyage. So we need to accelerate our astronaut to 30,000,000 metres per second, and decelerate them at the other end. Cheating and using Newton's laws of motion, the kinetic energy acquired by acceleration is 9 x 1017 Joules, so we can call it 2 x 1018 Joules in round numbers for the entire trip. NB: This assumes that the propulsion system in use is 100% efficient at converting energy into momentum, that there are no losses from friction with the interstellar medium, and that the propulsion source is external — that is, there's no need to take reaction mass along en route. So this is a lower bound on the energy cost of transporting our Mercury-capsule sized expedition to Proxima Centauri in less than a lifetime. To put this figure in perspective, the total conversion of one kilogram of mass into energy yields 9 x 1016 Joules. (Which one of my sources informs me, is about equivalent to 21.6 megatons in thermonuclear explosive yield). So we require the equivalent energy output to 400 megatons of nuclear armageddon in order to move a capsule of about the gross weight of a fully loaded Volvo V70 automobile to Proxima Centauri in less than a human lifetime. That's the same as the yield of the entire US Minuteman III ICBM force.
Re: (Score:2)
> What happens when the first generation of kids comes of age, notices they never gave consent to be confined to a ship for their entire lives, and decides to turn around?
There are major ethical problems with generational ships.
No human being on earth gives consent to be born either, and I personally think it's an analogous situation. I'm currently planning to not have children on the basis of this kind of consideration.
Re: (Score:2)
Compared to all the other engineering challenges packing a few thousand shelf-stable euthanasia modules should be pretty trivial.
Re: (Score:3)
It's theoretical - more an attempt to get potential ideas that might one day form the basis of an actual ship than anything else. Hypothetically speaking, before you would actually build something this you'd expect there to have been a few technological advances to both shorten the trip and confirm whether or not Proxima Centuri b is habitible or not.
Re: (Score:2)
They could turn around and come back. The question is what will they come back to? Is earth still habitable? If it is, are "earthlings" willing to share the planet with an 800 year old space faring civilization that probably looks nothing like earth civilizations anymore? If the ship is designed to withstand the rigors of space, they might even chose to not go back, but keep going until they do find a habitable planet. Maybe they don't want to leave space anymore and will use the resources of the planet to
We've seen it before, those who left not welcome (Score:2)
> are "earthlings" willing to share the planet with an 800 year old space faring civilization that probably looks nothing like earth civilizations anymore?
The book "Guns, Germs, and Steel" suggests no. A Pacific Islander population splintered, a group went off to colonize another yet-to-be-discovered island. They were successful and lost contact with the homeland. A very small number of generations later, three?, the group left behind discovered the colonized island. The people living on the island were peaceful and promptly conquered and enslaved by their still warlike relatives only a few generations apart.
> If the ship is designed to withstand the rigors of space, they might even chose to not go back, but keep going until they do find a habitable planet.
And we saw this with the Pacific Islanders too.
Re: (Score:2)
The one way trip requires 4.5 million tons of He3 and Deuterium, they'd need to either bring more than double that or find it there, and also remanufacture most of the 2.4 billion ton ship to bring it back to spec for the trip back. Actually though, I'm surprised at how llitle fuel they need for the trip.
Re: (Score:2)
Talking about 16 generations. Those people if they build a stable society won't have more connection to any planet other than old legend that there used to be a world beyond the spacecraft. They'll be native "spacecraftians", they'll just keep living there. Until their resources are exhausted, that is.
I personally don't believe the travel is possible with so few people. To support advanced machinery, one needs a population in the several millions and huge mining resources. Otherwise no steel mills, no concr
Re: (Score:2)
Earth could continuously transmit the latest knowledge to the ship throughout its journey. The signal delay would increase as the ship gets farther away, but Alpha Centauri is only 4.25 light years distant. That's not much lag if the main concern is keeping up on the latest advancements in research.
2-way communication is still not crazy unreasonable with an 8.5 year round trip delay.
The folks on the ship would have to put a lot of effort into education to be successful. I think the bigger issue is the et
Re: (Score:3)
> What do they do if they get to his planet and find out it can't support their life?
Well, they start terraforming, of course!
We've done that ... (Score:2)
>> What do they do if they get to his planet and find out it can't support their life?
> Well, they start terraforming, of course!
It's what the Pacific Islanders did. As part of a colonizing effort, or a survival kit if unintentionally stranded somewhere, they traveled with about a dozen or so plant species that provided sustenance and medicinals. Getting these into cultivation on a new island was a priority after landing.
Europeans did something similar during their colonization. Select a site to build, turn a few pigs loose in the area. Hell, sometimes they'd drop a few pigs on a promising location with plans to come back in a few
Re: (Score:2)
Yeah OK, sure. Those Pacific Islanders arrived at islands that already had everything needed to support life. They had plants and animals already living there, just not the specific plants that were desired.
Starting from a completely dead planet, probably with a poisonous atmosphere, is a completely different thing.
We've done this before, sort of ... (Score:2)
> What do they do if they get to his planet and find out it can't support their life? Do they stay in the system and live their lives in the ship? Do they turn around and return home? Go some place else?
Historically, the Pacific Islander migrations suggest the latter. Go some place else.
Re: (Score:2)
They'd get there, think it's not up to their standards of living, so turn back, to their beloved history books blue planet, and 400 years laters, when finally getting back to earth, they'd have a 'madagascar's penguins' moment "well this sucks"
Re: It will be financed (Score:2)
I think they prefer to be called artificial people.
So what happens when they get there? (Score:2)
They just turn around and come back?
Yeah, "designed" (Score:2)
Bunch of made up oie in the sky shit
Re: (Score:3)
> ... they can't get Viking to have power beyond our own solar system let alone another one....
Assuming you meant Voyager 1 and 2 (from the subject) and not the Viking probes that landed on Mars, their 3 RTGs (each) are still generating power, though now at about half what they did at launch due to radioactive decay (combined 470W in 1977 vs 225W in 2023) -- the half-life if Pu-238 is 87.7 years. It's just currently not enough to power everything and keep everything warm enough - but it's still enough to support some capabilities. Larger and/or more numerous RTGs could be used on future missions,
The operative word (Score:2)
"Could". I "could" become a billionaire. I could have monkeys fly out of my butt. These are all at the same level of likelihood.
Re: (Score:2)
"These are all at the same level of likelihood."
I disagree, we know that billionaire's exist, so that is at least a non zero level of likely. AFAIK, there is no documented case of monkeys flying out of anyone's butt, so I don't think it would be unreasonable to assign a zero level of likely to that.
Have none them every read scifi (Score:2)
Four hundred years is about 12 generations and 5 to 6 lifetimes. The number of things that could go wrong that have nothing to do with the physical design boggle the mind. Has their design accounted for the inevitable leakage of air and water over time, the potential growth of the population, the effects of radiation on the health and genetics of the crew, the need for artificial gravity, and the numerous other things that need to be considered. Even if all those things could be taken care of, it seems u
Re: (Score:2)
Aside from the points you mention, I was more concerned with human factors, psychological and psychiatric issues, societal, group dynamics and so on. Basically everyone going bonkers.
Re: (Score:2)
> need for artificial gravity, and the numerous other things that need to be considered.
Artificial gravity is somewhat provided by centrifugal force due to the rotation. However, the apparent gravity would be linear on the distance from the rotation axis, and there would be Coriolis effects that make the “gravity” behave strangely, especially if the angular rate is high and the radius is small.
Re: (Score:2)
For me the dead giveaway was it will be powered by fusion. Well, no, there are no working fusion reactors. None, zero. But then after their 80 year trial, maybe it will be available. That is 2 "fusion is only 40 years away" periods.
Poor presumptions (Score:2)
This ship design presumes technology not currently existing, but does so poorly.
The tech required for it is not significantly beyond the requirements for:
1) a solar system based laser to power a solar sail ship, that should be able to travel at 0.5% of the speed of light, enabling travel in less than 80 years, let alone 400.
2) medical technology to allow humans to live for up to 140 years in a controlled environment like a starship.
This combination would negate the need for a 'generation' ship, replacing it
Re: (Score:2)
> This ship design presumes technology not currently existing, but does so poorly.
For navigation it uses Tesla Autopilot, or will about two years after launch ....
Designed? (Score:2)
Anybody can come up with sketch for such a thing, which is what this is. The thousands upon thousands of issues to be solved before the construction of this ship could get going are not even mentioned in the proposal, much less addressed.
Not Clarke & "Rama"; O'Neill & "The High F (Score:2)
Clarke's vision of Rama in 1973 predates O'Neill's eponymous [1]conceptual station design [wikipedia.org] by one year, but it's a completely different model to this. Rama did not spin for gravity and was (internally) infinite in size, so probably wasn't really anything intended as something actually buildable so much as a fantastical McGuffin to facilitate the plot.
This design is much more akin to Gerard K. O'Neill's proposal for an *actual* space habitat consisting of two counter-spinning concentric shells to provide spi
[1] https://en.wikipedia.org/wiki/O'Neill_cylinder
Don't Forget Heinlein's "Orphans in the Sky" (Score:3)
Great read about the dangers that people are talking about even if the tech doesn't fail.
Re: (Score:2)
Did you read the same Rendezvous With Rama that I did? Rama definitely spins on its axis to create gravity for the interior walls. Hence the big staircase the LED down from the axis to the interior on the one end.
Re: (Score:2)
"that led down.". Sigh. Google keyboard is really bad sometimes. AI will make it better I'm sure.
I've got some tickets to sell (Score:2)
Anybody want to buy some? These tickets are guaranteed to get you to Alpha Centauri, or your money back. If you should choose to receive a refund after your 70 years on Antarctica, please contact my grandchildren.
How does 70 years on Antarctica help anything? (Score:2)
However long your first crew stays in isolation in Antarctica, those people won't be on the ship, their children, and their children's children will. Just because Great-Granddad did fine, has no bearing on whether the children will "do fine." As every parent knows, each child is unique, even when they have the same parents.
No, if you're going to get on board this thing, just...do it already. It's a marathon, not a sprint. Whatever happens, you're just going to have to make it work.
Re: (Score:2)
Genetics.
Descendants of those that did well in Antarctica isolation are more likely to do well in space isolation than those that did not.
Re: (Score:2)
Do you have children? Are they like you?
One thing you find out, being a parent, is that children have a mind of their own. They have very different strengths and weaknesses than you do.
I have two boys. I handle money well, one of my sons does also, and one does not. I'm an extrovert, one of my sons is an extrovert, the other is not. I'm terrible at art, but both my sons are excellent artists.
No, "doing well with isolation" is not likely to be a genetic trait.
HOA disputes (Score:2)
Hope your neighbor doesn't build an unsightly fence, or plant a tree too close to your property line. It could get ugly.
I already played that game (Score:3)
I already played [1]that game [steampowered.com] and so should you!
Building something like this is a bigger engineering challenge than we're currently capable of, but I think that in time we'll do it. Some crazed rich fool will pay for it and even crazier fools will fight for the opportunity to go along for the ride. It's in our DNA.
[1] https://store.steampowered.com/app/648410/Colony_Ship_A_PostEarth_Role_Playing_Game/
Only once 'though' changes into 'known' (Score:2)
Thought to be habitable is not good enough.
They "studied" Douglas Adams (Score:2)
Its an ambitious idea, but we should build more to be rid of all the useless people.
Oh really?? (Score:2)
To travel 40 trillion km in 400 years means an average speed of about 3168 km/s. And this ship is 58km long?? let's assume it's 58km x 100m x 100m with an average density half that of water. That gives us a mass of about 290 billion kg. To accelerate 290 billion kg up to 3168 km/s will take about 1.46 * 10^24 joules, or roughly as much energy as everyone on Earth consumes in 2500 years.
Good luck with that.
Re: (Score:2)
Just read the spec; my mass estimate was low. They're claiming 2.4 billion tons which is 2.4 * 10^12 kg. So I under-estimated the energy almost by a factor of 10; we're looking at about as much energy as everyone on Earth consumes in 20,600 years.
Re: (Score:2)
Now add the energy it takes to put that mass into orbit around earth to construct the ship in the first place.
I suppose they're banking on a space elevator.
Perfect ... (Score:2)
... for the telephone sanitizers.
I read the novels (Score:2)
It will be fun. :-)
There is a more realistic way... (Score:2)
Send fertilized eggs cryo frozen, have a massive AI, and a few robots that the AI controls. "grow the humans" when they get there. It may not be possible at the moment, but should be possible in 20 years or so, the ship would be 100x smaller than the one they envision. I don't think generational ships is feasible for a lot of reasons. If they get there, and there isn't a habitable planet, they could possibly re-fuel and go to the next system.
a commonplace trope (Score:2)
If you read much science fiction you will have seen a lot of stories about interstellar flight like this. And there are all kinds of solutions, many of which involve hibernation or cold storage of the crew while some kind of AI handles the navigation and ship systems. Usually it goes haywire in order to generate drama.
Sometimes there's a rotating set of human skeleton crew that gets awoken to make sure things are going okay. In the novels there will be all kinds of tension associated with that, or the ship
Re: (Score:2)
> Travel outside the solar system simply is not practical without faster than light speeds, by orders of magnitude.
Practical, no, but that doesn't necessarily mean it isn't worth considering. The real question is whether there's enough data to determine that it would sustain life, and if not, whether you would have be able to bring along enough fuel to turn around and come back, while still being able to handle any other navigation needs along the way (e.g. avoiding stray asteroids). I don't even have any concept of the fuel requirements for something like that, because there's no way to know what you're going to enco
Re: Absolutely absurd! (Score:1)
The Ramans do everything in threes.
Re: (Score:3)
Since when has humanity ever cared about doing only what's practical?
Re: (Score:2)
> Travel outside the solar system simply is not practical without faster than light speeds
That's sort of the point of the exercise. Just how impractical is it and what would it take to make it practical?
I can certainly throw darts at it. For one, when accelerating, the ship is essentially a 58km tall tower. We don't know how to build a tower that tall which won't collapse under its own weight (even at 0.1 g). No doubt they did the math about how to build such a thing but color me skeptical.
Fusion reactors? A mere 20 years away (and always will be).
Keeping 2,400 people from killing each other for
Re: Absolutely absurd! (Score:2)
prototypes.
maybe build a test vehicle to scale that would shuttle back and forth to mars