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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)

#181

Post by silverquiet »

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…

> 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.

That isn't really different from the way things are now. We are, in fact, traveling through the galaxy for many generations and none of us signed up for it. We just happen to be on a largeish ship and have no destination.

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

#182

Post by folli »

Sharlin wrote: post #158
amelius wrote: post #91

Earlier quoted context omitted.

What are the chances of hitting a small meteorite or part of it, traveling now at relativistic speeds wrt you?

Micrometer-scale specks of dust would hit you like they were armor piercing tank gun rounds. The usual shielding proposed is ice. Lots of ice.

Why ice?

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

#183

Post by kristopolous »

This makes the Theia hypothesis all the more extraordinary https://en.wikipedia.org/wiki/Theia_(hypothetical_planet)

I believe the scientific record is drawing a consensus on this as the moon's origin but the wild sparseness of space just makes this sound really unusual.

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

#184

Post by aledalgrande »

This is super cool. It's crazy to think about asteroids in any depiction of the solar system look so packed that I thought a spaceship would never be able to pass through unscathed, but here it's all black because they are basically irrelevant lol

Also crazy how far Jupiter's gravity can keep a moon??

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

#185

Post by wafflemaker »

lisper wrote: post #173
amelius wrote: post #3

Make sure you press the "c" button in the bottom right. Light is incredibly slow, and everything seems out of reach. I think we'll have a holodeck before we reach another star. And maybe that'll be enough.

It only seems incredibly slow in this model because it doesn't take special relativity into account. If it did, then as you approached the speed of light the Lorentz contraction would make wherever you are heading appear less far away. You can in theory get anywhere in the universe in an arbitrarily short amount of proper time your own reference frame. Of course, you might not survive the G-forces, but that's another…

Don't forget gravity drive. No more Gs. And the same technology would give us real artificial gravity, not this nauseous rotation artificial gravity.

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

#186

Post by Sharlin »

folli wrote: post #182
Sharlin wrote: post #158

Earlier quoted context omitted.

Micrometer-scale specks of dust would hit you like they were armor piercing tank gun rounds. The usual shielding proposed is ice. Lots of ice.

Why ice?

Mostly that it's plentiful, ablative, expendable, plus good radiation shielding (yeah, cosmic ray protons are really going to mess things up at relativistic speeds too unless there's enough mass to stop them).

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

#187

Post by aledalgrande »

amelius wrote: post #3

Make sure you press the "c" button in the bottom right. Light is incredibly slow, and everything seems out of reach. I think we'll have a holodeck before we reach another star. And maybe that'll be enough.

Need that warp drive

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

#188

Post by tanewishly »

nilamo wrote: post #147
raxxorraxor wrote: post #74

Earlier quoted context omitted.

Not out of reach if you get very close to light speed. Time would advance very slowly for you, so counterintuitively it is possible to travel 5000ly in your life time. Although for everyone else at least 5000 years will pass, so better say goodbye to family and friend. Hm, not sure if that is really less depressing... Also light isn't slow. A photon instantly travels to the end of time and yet it still takes a few mi…

> Hm, not sure if that is really less depressing... A starship capable of such a journey is surely large enough to bring all your friends and family along, colony-ship style.

We're already on that starship. Our engine is about 8 lightminutes away. All we need is to figure out how to steer this thing - and how to not wreck it while en route.

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

#189

Post by jandrese »

jandrese wrote: post #140
jadbox wrote: post #99

Unrelated, but the Elon dream of getting a human colony on Mars seems beyond imagination. Ignoring safety of such a long travel, the radiation issue of Mar's surface, and the massive infrastructure to have a self-sustainable biosphere (also somehow protected from radiation) to recycle enough oxygen, we still have to deal with the immense number of failures that could happen with no way to send help. Like, building a…

> Like, building a fully self-sustainable underwater city or moon base would be far more in reach. It feels that SpaceX should start with prototyping these safer alternatively before overreaching to something 100x more challenging and dangerous. I've been beating this drum for years. Elon is 100% focused on building the rocket that can get to Mars and neglecting absolutely everything else about the project. Where is…

The problem with Mars is that if something goes wrong you can't just "fly back on the rocket". The launch windows are 2 years apart. You either fix it in place or you die.

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

#190

Post by aledalgrande »

ryandrake wrote: post #103
causal wrote: post #88

Earlier quoted context omitted.

Yeah if you have a body that can tolerate sudden jumps between reference frames you could pretty much explore the entire galaxy trivially, so long as you don't mind that few places will stay the same long enough to visit twice.

You wouldn't need a sudden jump. If you had a rocket that accelerated at a pleasant 1G forever, you could reach and stop at the center of the milky way in about 20 (your time) years, and you could reach and stop at the Andromeda galaxy in about 28 years. Play around with some of the online space travel relativity calculators--it's wild! Of course building and fueling such a rocket is what's totally out of reach.

Is there drag in space? I.e. would you need increasing energy to accelerate at a constant rate as the speed goes up?
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