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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)

#91

Post by amelius »

Sharlin wrote: post #87
amne wrote: post #78

Earlier quoted context omitted.

How would that feel as a traveler? Does all motion slow down to a crawl, all sub-atomic particles just "freeze" and essentially your thoughts and body aging too? So it would seem like you got there in an instant? For sure you're not just sitting there watching people get born, live and die in second and shrugging your shoulders.

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.

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

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

#92

Post by j_m_b »

One of my favorite visualizations of the scale of the solar system is from Stephen Hawking's Genius.

https://mass.pbslearningmedia.org/resource/hawking_genius_ep...

It's a hands-on, practical example of how far things are away that we can easily visualize. I highly recommend the rest of the series as well. It's one of the best science shows ever produced. It shows the practical path of scientific discovery. You can watch is on the PBS app, which requires a $60 a year pass. Highly worth it. (I have no affiliation with PBS)

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

#93

Post by kqr »

amelius wrote: post #91
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.

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

Extremely low. Space is very empty.

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

#94

Post by kqr »

gwbas1c wrote: post #81
munksbeer wrote: post #9

Earlier quoted context omitted.

> Light is incredibly slow, and everything seems out of reach. Yes, agreed. I find it a little depressing. An unimaginably huge universe, tantalisingly there, but completely out of reach.

It makes me wonder what kind of "life" could perform interstellar travel? I used to imagine a spaceship being alive, with people inside being analogous to "cells" in a multicellular organism. Perhaps this is really how AI achieves consciousness?

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

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

#95

Post by dahart »

susam wrote: post #25

When I was dabbling with POV-Ray many moons ago, I drew the planets of our solar system to scale with it. You can see it here: https://github.com/susam/pov25#planets A friend once asked if I couldn't show the planets in orbit rather than lying flat on a plane. I could, of course, but this is ray tracing. What do planets actually look like to human eyes from Earth? Just tiny dots. If I were to show them in their prope…

Would you have to use double precision to ray trace the planets in their proper orbits at scale using either perspective or orthographic projection? With the ratio of Neptune’s distance from the sun to its radius being almost 2M, I’m guessing fp32 rounding would turn Neptune into a couple of squares if the sun was at the origin. What other challenges would there be? Maybe I’ll try it today just for fun.

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

#96

Post by TheOtherHobbes »

amelius wrote: post #91
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.

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

There's about one particle of dust per million cubic metres. c is about 300 million metres/second. So even at 0.5c that's still a lot of particle collisions per second, each having significant kinetic energy.

Basically it would be like flying through explosive sandpaper. Each dust particle would be reduced to plasma, which creates problems of its own.

If you're accelerating there's also the Unruh Effect, which will raise the perceived temperature. By a lot.

There's no way to make this work with any kind of engineering we know about today.

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

#97

Post by brazzy »

kqr wrote: post #93
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?

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%".

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

#98

Post by TheOtherHobbes »

kqr wrote: post #94
gwbas1c wrote: post #81

Earlier quoted context omitted.

It makes me wonder what kind of "life" could perform interstellar travel? I used to imagine a spaceship being alive, with people inside being analogous to "cells" in a multicellular organism. Perhaps this is really how AI achieves consciousness?

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.

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

#99

Post by jadbox »

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 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.

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

#100

Post by ck2 »

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.

Alternate view:

be thankful things are far apart

a gamma-ray burst from a collapsing star closer than 200 light years away would destroy ALL life on earth

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