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Project Hyperion: Interstellar ship design competition

projecthyperion.org

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Re: Project Hyperion: Interstellar ship design competition

#101

Post by scythe »

JumpCrisscross wrote: post #29
virgildotcodes wrote: post #12

Earlier quoted context omitted.

Reading through this in detail just cements that we are never leaving this solar system unless we discover some new physics to get around our speed limitations.

> we are never leaving this solar system unless we discover some new physics to get around our speed limitations The winning proposal coasts at 0.01c. Propulsion systems--not the speed of light--and thus engineering, not phsyics, are the relevant limitors.

Relativity isn't the problem. The problem is that hitting a grain of sand at 0.1 c delivers the energy of several tonnes of TNT.

My guess is that we will colonize the asteroid belt (Palladium! So much palladium!) and send lots of interstellar probes long before we try to send humans outside the solar system. Right now we're like a village that lives by a river and has never reached the mouth talking about sailing across the ocean. There are a lot of intermediate stages.

Re: Project Hyperion: Interstellar ship design competition

#102

Post by vl »

codeulike wrote: post #2

Link to Canva presentation for the winning entry https://www.canva.com/design/DAGmr3ubC8E/LHHAeeAIGGQe_TkZVs-...

Cool concept, but some things are just strange:

Power provided by toroidal nuclear fusion reactors in the outer shell of the living module, but why do you need such reactors if your primary propulsion is provided by Helium 3 - Deuterium Direct Fusion Drive? If you have direct fusion technology, you don't need toroidal reactors.

Rotating inner shells mechanically for 400 years is terrible design, it's much easier just to rotate entire structure. Once it's going it keeps rotating inertially!

Another comment points to error in speed calculation - at declared acceleration they should go at 0.1c, not 0.01c!

And what is missing of course is the calculation of how many years of current world's GDP is required to complete such project event if all yet-to-be invented technologies exist.

Re: Project Hyperion: Interstellar ship design competition

#103

Post by arjie »

One thing that I think is fun now that we have embryo freezing is that we can transport absolute masses of genetic diversity into the future, so even a small crew of a generation starship need not worry about interbreeding risk. Social risks abound, of course, but we could easily supply hundreds of thousands of embryos into the far future so that concerns of a minimum viable population are no longer valid.

That eliminates biology as a constraint. What a life for our descendants so consigned, generations to live and die on a ship so that their descendants in turn could one day revolve around a foreign sun. I'm sure at some nth generation they will resent us for sending them away from the happiness of Spaceship Earth.

It would be an amusing result if the only ones with the fortitude necessary to endure this are those religious enough in belief and purpose.

Re: Project Hyperion: Interstellar ship design competition

#104

Post by amenhotep »

vl wrote: post #95
AtlasBarfed wrote: post #82

Earlier quoted context omitted.

Where is the propulsion system design? Are all of these handwaving propulsion? They seem to all be habitat designs. Ok I'll take my shot at propulsion: Pulse nuclear BUT: For acceleration, we have a launch gun that fires more fuel at the ship, and the ship catches the fuel, imparting momentum from the catch, and more fuel for acceleration. For deceleration, we have pellets that it catches up to and uses the catching…

The drive in this design is not yet invented Helium 3 - Deuterium Direct Fusion Drive. In your design how is it going to catch up to pellets if it's decelerating? I.e. pellets need to be pre-decelerated for this. Which raises the question, would it be cheaper just to bring all deceleration fuel onboard.

You'd spend years firing pellets in advance of the voyage, on the same trajectory but moving a little slower than the ship you plan to launch. Time it all so you catch up with the first of them just as you want to start decelerating.

Re: Project Hyperion: Interstellar ship design competition

#105

Post by svachalek »

Ancalagon wrote: post #76
TuringNYC wrote: post #70

Earlier quoted context omitted.

I was always curious about this. In some of the star wars movies, you dont see any spin, yet they are not floating around (e.g., notice how Orson Krennic has a backdrop of a planet, isnt floating, yet the planet isnt spinning https://allfortheboys.com/ben-mendelsohn/ ) I know Interstellar did not ignore the spin, but do movies like Star Wars just ignore the entire concept?

I think they have artificial gravity in star wars iirc

And anti-gravity, as seen in the many machines and craft that easily hover around.

Re: Project Hyperion: Interstellar ship design competition

#106

Post by svachalek »

jmyeet wrote: post #69

An interstellar ship is indistinguishable from a generational colony ship because there's no way to realistically travel between stars in timelines that don't span generations unless we extend human lifetimes to centuries or longer. That's possible but doesn't change the trael times. It just means you live to the destination rather than your descedants do. And let's aside the serious ethical issue of you choosing to…

It's interesting how frequently the issue of unborn children's consent is brought up. This consent is impossible, it's never existed and never will exist, and the only alternative seems to be nihilism.

Re: Project Hyperion: Interstellar ship design competition

#107

Post by nn3 »

vl wrote: post #102
codeulike wrote: post #2

Link to Canva presentation for the winning entry https://www.canva.com/design/DAGmr3ubC8E/LHHAeeAIGGQe_TkZVs-...

Cool concept, but some things are just strange: Power provided by toroidal nuclear fusion reactors in the outer shell of the living module, but why do you need such reactors if your primary propulsion is provided by Helium 3 - Deuterium Direct Fusion Drive? If you have direct fusion technology, you don't need toroidal reactors. Rotating inner shells mechanically for 400 years is terrible design, it's much easier just…

If you would spin the whole structure you couldn't have multiple shells all with 1G on their surface. The required spin speed for 1G depends on the diameter. But their whole concept is built around multiple shells, which is clear from the name.

Regarding the GDP needed once you have a working "mine from the moon and send to orbit" economy it doesn't seem to be too bad. The assumption would be that a lot of technology is already developed for other projects. Launching it all from earth obviously wouldn't be possible even with vastly cheaper launch. That's why they put the build into the moon-earth L1 lagrange point to be easily reachable from the moon.

For propulsion and reactors, but there are multiple projects today working on all of this. Building a life support system for 400 years is still an unsolved problem however.

Re: Project Hyperion: Interstellar ship design competition

#108

Post by bobabob »

383toast wrote: post #72
bobabob wrote: post #62

Why does it say the Chrysalis spends 400 years in inertial age at 0.01c if it accelerates for 1 year at 0.1g? That should bring it to actually ~0.1c and the whole trip would take less than 15 years.

Doesn't it need to slow down

Yes, and that should also take 1 year.

Re: Project Hyperion: Interstellar ship design competition

#109

Post by [deleted] »

munificent wrote: post #100
JumpCrisscross wrote: post #29

Earlier quoted context omitted.

> we are never leaving this solar system unless we discover some new physics to get around our speed limitations The winning proposal coasts at 0.01c. Propulsion systems--not the speed of light--and thus engineering, not phsyics, are the relevant limitors.

I am increasingly certain that culture is by far the biggest limiting factor when it comes to large-scale problem solving now and in the future. We couldn't even reliably get people to put a piece of fabric over their face to stop killing their own relatives. Even if we could build a generation ship, it would turn into an Event Horizon hellscape if we don't figure out better cultural, communication, and sociological…

[deleted]

Re: Project Hyperion: Interstellar ship design competition

#110

Post by jmyeet »

protocolture wrote: post #93
jmyeet wrote: post #69

An interstellar ship is indistinguishable from a generational colony ship because there's no way to realistically travel between stars in timelines that don't span generations unless we extend human lifetimes to centuries or longer. That's possible but doesn't change the trael times. It just means you live to the destination rather than your descedants do. And let's aside the serious ethical issue of you choosing to…

The winning design assumes redundant toroidal fusion reactors.

Having a fusion engine or fusion reactor is basically hand-waving away the energy problem.

Controlled fusion has a fundamental problem: neutrons. Even if you solve the problem of container destruction (ie neutron embrittlement), which is significant, you still face the problem of significant energy loss to the system through high-energy free neutrons.

Stars solve this problem by simply being really large so a free neutron can't really go that far without hitting another nucleus, particularly because fusion happens at the core.

The hope with commercial fusion research is that we can somehow avoid the container destruction issue and have sufficient energy generation (given the energy inputs) despite the free neutron energy loss but it's unclear if that'll ever happen.

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