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If the moon were only 1 pixel: A tediously accurate solar system model (2014)

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Re: If the moon were only 1 pixel: A tediously accurate solar system model (2014)

#121

Post by danudey »

TheOtherHobbes wrote: post #98
kqr wrote: post #94

Earlier quoted context omitted.

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

To make a generation ship work you have to build a self-contained ecology that is stable and self-repairing, inside mechanical and software systems that are fault tolerant and either extremely redundant or self-repairing, run by a political and social system that is also fault-tolerant and self-repairing. We know how to do exactly zero of those things.

There's a CRPG I've been meaning to play where this is basically the plot; there was a generation ship, it was heading towards some planet or another, but the social and political structure on the ship broke down at some point and now there's no one actually in charge, the ship is getting run down, and they probably blew past their destination a hundred years ago if they were even still on course at all.

I remember someone pointing out that a generation ship could be problematic because you have one generation who decides to launch this expedition but will never see the end, multiple generations who didn't choose this life and won't get to see the benefits, and then one generation who actually gets to the planet but might not even want to be there. Without some kind of cryogenic sleep or relativistic speeds the whole thing might fall apart just because most of the people involved "didn't sign up for this" but they have to toil away anyway for someone else to benefit from it.

Re: If the moon were only 1 pixel: A tediously accurate solar system model (2014)

#122

Post by literalAardvark »

ant6n wrote: post #72
dylan604 wrote: post #52

Earlier quoted context omitted.

Plenty of time for reflection on one’s choices in life that put them in that situation.

Especially generation 143 of 330, they can definitely spend their whole life on that reflection.

Speaking of which, Peter Watts' Sunflower Series has a great and short enough hard-ish scifi story about just such a ship.

Re: If the moon were only 1 pixel: A tediously accurate solar system model (2014)

#123

Post by M95D »

eddd-ddde wrote: post #118
johnnyjeans wrote: post #117

Earlier quoted context omitted.

Is light slow? Or is the human perception of time just scaled down as a result of our rapid metabolism and infinitesimality? People historically mistake plants for being inanimate things with no reactivity, that they are far more simple and stupid than they truly are. Outside of a few exotic examples, plants simply operate on a wider timescale that's basically imperceptible without careful and particular observation.…

I always think of those motor proteins moving along slowly inside our bodies, and wonder if maybe we are just the motor proteins of the cosmic scale.

We have a long way to go before we learn to move a star (or a rosette).

https://en.wikipedia.org/wiki/Stellar_engine

https://en.wikipedia.org/wiki/Klemperer_rosette

Re: If the moon were only 1 pixel: A tediously accurate solar system model (2014)

#124

Post by IAmBroom »

eddd-ddde wrote: post #118
johnnyjeans wrote: post #117

Earlier quoted context omitted.

Is light slow? Or is the human perception of time just scaled down as a result of our rapid metabolism and infinitesimality? People historically mistake plants for being inanimate things with no reactivity, that they are far more simple and stupid than they truly are. Outside of a few exotic examples, plants simply operate on a wider timescale that's basically imperceptible without careful and particular observation.…

I always think of those motor proteins moving along slowly inside our bodies, and wonder if maybe we are just the motor proteins of the cosmic scale.

Dude, pass the duchy.

Re: If the moon were only 1 pixel: A tediously accurate solar system model (2014)

#125

Post by IAmBroom »

seanw444 wrote: post #107
Sharlin wrote: post #87

Earlier quoted context omitted.

You’d feel nothing out of the ordinary whatsoever. The starscape outside the ship would look strange though, shrinking into a small, blueshifted patch of sky straight ahead, while stars behind you would redshift out of the visible range. Everything moving at very low speeds relative to you would indeed appear to happen really fast.

If the light behind you redshifts out of the visible spectrum, would the light in front of you blueshift into dangerous territory? X-rays, gamma rays, etc?

Yes. To some degree.

Re: If the moon were only 1 pixel: A tediously accurate solar system model (2014)

#126

Post by amelius »

brazzy wrote: post #97
kqr wrote: post #93

Earlier quoted context omitted.

Extremely low. Space is very empty.

But it's also very big , and GP doesn't even specify how far of a trip they're asking about nor how small a meteorite. "Extremely" and "very" don't cut it here. This is beyond the human ability to guess. You'd actually do at least some back-of-the-napkin math to give a real answer, and with a far enough trip, the answer may well become "Almost 100%".

How far a trip: maybe start with the nearest star.

Re: If the moon were only 1 pixel: A tediously accurate solar system model (2014)

#127

Post by IAmBroom »

zwily wrote: post #116
mock-possum wrote: post #106

Earlier quoted context omitted.

That doesn’t make sense - if you were traveling at the speed of light, it would take you 5000 years to travel 5000ly - longer if you were just ‘very close’ to C. Time wouldn’t advance slowly for you, it wouldn’t advance perceptively different at all - you’d still live every second of those 5000 years.

Read up on time dilation and special relativity. Time absolutely does pass slower for you as you accelerate.

You two are talking about different meanings of "time".

Traveling 5,000 LY at 0.5 c will cause you the spaceship pilot to age 20,000 years. It's non-relativistic, inside that inertial frame. Clock second hands still sweep slow but noticeable circles.

Meanwhile, everyone outside of the spaceship is happening FAST, by your observations. You'll see stars turn red and go supernova.

Re: If the moon were only 1 pixel: A tediously accurate solar system model (2014)

#128

Post by ByThyGrace »

tomxor wrote: post #69
darajava wrote: post #61

Earlier quoted context omitted.

Incredible - how does this work?

You mean technically? I should have posted the beta dwitter link which has the "compress" toggle, because most dweets are unicode packed. https://beta.dwitter.net/d/26521 Here's the js anyway: for(i=10;i--;x.fillStyle=R(i-8||255),x.beginPath(x.fill()))x.arc(960+[45,29,14,8,2,1.5,1,.6,0,0][i]*1e5*S(t/5e3/[165,84,29,12,2,1,.6,.2,1,1][i]),540,[24,25,58,69,3.4,6.4,6,2.4,696,2e3][i],0,7) This one is actually relatively si…

I presume including Pluto's parameters in the array is both a rebellious statement and a brag. ("Yes, my JS snippet could have been even shorter if you asked the IAU.")

Re: If the moon were only 1 pixel: A tediously accurate solar system model (2014)

#129

Post by IAmBroom »

ClumsyPilot wrote: post #75
jordigh wrote: post #71

Earlier quoted context omitted.

I can't tell if you're joking or if you know something nobody else does. As far as I know, anything going faster than the speed of causality violates causality. So what are you talking about?

> violates causality But we don’t know that casualty is a law of physics, do we?

Only inasmuch as we don't know that gravity and the Strong Nuclear Force aren't.

Re: If the moon were only 1 pixel: A tediously accurate solar system model (2014)

#130

Post by datameta »

danudey wrote: post #121
TheOtherHobbes wrote: post #98

Earlier quoted context omitted.

To make a generation ship work you have to build a self-contained ecology that is stable and self-repairing, inside mechanical and software systems that are fault tolerant and either extremely redundant or self-repairing, run by a political and social system that is also fault-tolerant and self-repairing. We know how to do exactly zero of those things.

There's a CRPG I've been meaning to play where this is basically the plot; there was a generation ship, it was heading towards some planet or another, but the social and political structure on the ship broke down at some point and now there's no one actually in charge, the ship is getting run down, and they probably blew past their destination a hundred years ago if they were even still on course at all. I remember s…

What of the "just so" attitude of a child growing up? Everything is taken at face value, there is no comparison, only stories (unless you have a catalogue of 30EB of 8K earth footage or something to that effect for them to fawn over). They don't have the reference frame for other situations for a while, perhaps long enough to not be able to see things differently?

This makes me think of multi-generational migrations north out of Africa. There's only so much that can be passed orally losslessly. Eventually the group in north siberia after 20K years doesn't see living any other way.

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