"Promising hints of life on distant planet"

[Ryujin]

The problem isn't getting enough space. Ceres has a volume of about 27% of that of the Moon. And, if that's not enough, if you can move an asteroid to another star, you can move them around here until you had a glob of them that was big enough.

The real problem is that if - how the heck do you move an asteroid to another star?

 

[MarkB]

The problem isn't getting enough space. Ceres has a volume of about 27% of that of the Moon. And, if that's not enough, if you can move an asteroid to another star, you can move them around here until you had a glob of them that was big enough.

The real problem is that if - how the heck do you move an asteroid to another star?

Yeah, while an asteroid solves a lot of problems in terms of better shielding against things like radiation and high-velocity particle collisions, it's also a lot harder to move than a similarly-sized ship.

Also, I seem to recall seeing that our current understanding of large asteroid formation has accretion of smaller objects playing a much larger part than was previously believed, so while Ceres almost certainly has a decently-sized core of solid rock sufficient to house a generational colony, it may be deeply buried beneath a layer of compacted rubble, which would make even getting to that solid part a significantly greater challenge, much less clearing sufficient debris to attach huge rocket motors to it securely.

 

[Stalker0]

The short answer here is we do not know. I have heard some estimates that a stable generation ship or colony would need a population of a million or so, just to have the range of technical specialists over the time frame. we know even less about keeping a stable ecology over anytime frame.

If we are this level of sci-fi, you could likely invoke genetic engineering to help the skills you need and accentuate the species diversity. or just rely on AI for the technical expertise.

 

[UngainlyTitan]

If we are this level of sci-fi, you could likely invoke genetic engineering to help the skills you need and accentuate the species diversity. or just rely on AI for the technical expertise.

From an engineering perspective AI might have a lot easier time of it than us squishy humans

 

[Kaodi]

I have not read the whole thread but is this talk of sending a generation ship operating on the assumption that we had previously sent mechanical probes to tell us in detail about the world we were trying to travel to? So we are not sending generation ships on exploration missions, right?

Anyway... what are the odds that quantum entanglement communications would actually work?

 

[Morrus]

Anyway... what are the odds that quantum entanglement communications would actually work?

As I understand it, and I'm not a physicist, but zero. The basic setup prevents an exchange of information because a key/reference would need to be transmitted also, and that would be limited to light speed. You can 'receive' a 1 or a 0 (a particle spin of one way or the other), but you can't know what that means or what's happening at the other end. And you can't control it in advance and say 'if it's 1, invade; if it's 0, send cakes' because you don't know what the spin at the sending end is until you look at it. So you'd look at a particle, it's spinning clockwise, and you'd be, like, "cool, cool." There's a lot more nuance to it than that; this is a terrible explanation. Hopefully one of the actual physicists can explain better (or correct me).

 

[Ryujin]

As I understand it, and I'm not a physicist, but zero. The basic setup prevents an exchange of information because a key/reference would need to be transmitted also, and that would be limited to light speed. You can 'receive' a 1 or a 0 (a particle spin of one way or the other), but you can't know what that means or what's happening at the other end. And you can't control it in advance and say 'if it's 1, invade; if it's 0, send cakes' because you don't know what the spin at the sending end is until you look at it. So you'd look at a particle, it's spinning clockwise, and you'd be, like, "cool, cool." There's a lot more nuance to it than that; this is a terrible explanation. Hopefully one of the actual physicists can explain better (or correct me).

In code terms you could do something like make every 17th bit be a guaranteed 1 or zero, thereby giving the primer for how to assess the incoming data. If it's more complex than that, and I don't know as I'm not up on the physics involved, you could similarly make every 17th bit be whatever fixed state applies (angle, energy state, whatever).

 

[Morrus]

In code terms you could do something like make every 17th bit be a guaranteed 1 or zero, thereby giving the primer for how to assess the incoming data. If it's more complex than that, and I don't know as I'm not up on the physics involved, you could similarly make every 17th bit be whatever fixed state applies (angle, energy state, whatever).

I don’t follow that at all. But every science communicator/physicist (Neil deGrasse Tyson, Prof. Brian Cox, etc) on every podcast I’ve ever heard talking about this topic has maintained firmly that communication is logically impossible because the key also needs to be transmitted to allow you to decode the spins, and you can’t do that in advance of observing the particles (which is the instant of communication). I’m not informed enough to defend that assertion though.

 

[MarkB]

As I understand it, and I'm not a physicist, but zero. The basic setup prevents an exchange of information because a key/reference would need to be transmitted also, and that would be limited to light speed. You can 'receive' a 1 or a 0 (a particle spin of one way or the other), but you can't know what that means or what's happening at the other end. And you can't control it in advance and say 'if it's 1, invade; if it's 0, send cakes' because you don't know what the spin at the sending end is until you look at it. So you'd look at a particle, it's spinning clockwise, and you'd be, like, "cool, cool." There's a lot more nuance to it than that; this is a terrible explanation. Hopefully one of the actual physicists can explain better (or correct me).

Why do you need to know whether it's a zero or one? So long as you're getting some signal through, and can tell "right now there's a signal coming through, and now the line is dead", you can just revert to Morse code - brief or long bursts of signal are dots and dashes. Or zeros and ones if that's your preferred flavour.

 

[Reynard]

Yeah, while an asteroid solves a lot of problems in terms of better shielding against things like radiation and high-velocity particle collisions, it's also a lot harder to move than a similarly-sized ship.

No it isn't. Mass is mass. it requires exactly the same force to accelerate regardless of its origins or configuration.

You don't need to use a moon sized asteroid as the core of a generation ship -- just something big enough to hollow out and fill withy humans, hydroponics and CO2 scrubbers. A reasonable sized asteroid or comet as a foundation solves 2 problems that a manmade ship require a lot of engineering to solve: protection from cosmic rays, and the ability to withstand the impact of the interstellar medium at high velocity.