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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)

#101

Post by [deleted] »

Reubachi wrote: post #68
sestep wrote: post #36

Earlier quoted context omitted.

Naive question: is accelerating at 1G continuously within the range of what we consider possible?

Amazingly, yes, in a few ways (the mechanics are possible). But no in as many ways. (Fuel, sustainability, tracking) The greater barrier is that the nature of the expansion of the universe prevents any real interstellar travel that has a "destination" in mind. Of course we might have some "FTL" or "near light speed" travel in futre, but if the universe is expanding infintely from every point in space at light speed,…

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

#102

Post by brazzy »

Reubachi wrote: post #68
sestep wrote: post #36

Earlier quoted context omitted.

Naive question: is accelerating at 1G continuously within the range of what we consider possible?

Amazingly, yes, in a few ways (the mechanics are possible). But no in as many ways. (Fuel, sustainability, tracking) The greater barrier is that the nature of the expansion of the universe prevents any real interstellar travel that has a "destination" in mind. Of course we might have some "FTL" or "near light speed" travel in futre, but if the universe is expanding infintely from every point in space at light speed,…

This is not true. Expansion does not affect gravitationally bound structures. Our galaxy, and even the other galaxies in our local cluster, will stay in reach.

Source: https://www.reddit.com/r/askscience/comments/sr7fuo/is_there...

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

#103

Post by ryandrake »

causal wrote: post #88
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…

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.

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

#105

Post by brazzy »

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…

It's very clearly not "beyond imagination". It doesn't require any fundamentally new technology.

It may well be beyond our ability to practically apply those technologies at the required scales and reliability levels, but that's hardly unimaginable.

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

#106

Post by mock-possum »

raxxorraxor wrote: post #74
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.

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…

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.

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

#107

Post by seanw444 »

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.

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?

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

#108

Post by ryandrake »

Sharlin wrote: post #90
sheepscreek wrote: post #53

Earlier quoted context omitted.

Not with light speed travel. At even 1% the speed of light, the travel time diminishes significantly: - Titan, Io and Ganymede are only 2.5 days away - Pluto is about 23 days Edit: Even at such speeds, we still can’t visit a nearby star system in a reasonable time-frame. Oh well.

Traveling at .1c within the solar system wouldn’t really be feasible due to the need to accelerate and decelerate. Not for meatbag ships anyway.

There's nothing about 0.1c or even 0.999c travel that's detrimental to meatbags. They would both feel exactly the same to the traveler. If your (for now) imaginary rocket could accelerate at a constant, gentle 1G, you could reach 0.1c in about a month (traveler's time), and you could reach 0.999c in about 44 months. Building and fueling such a rocket is the hard part.

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

#109

Post by justusthane »

barrenko wrote: post #40
pdpi wrote: post #18

Earlier quoted context omitted.

> would just zoom it all in a minute, The Earth is about 8 light-minutes away from the Sun :)

I am not liking this fact.

The sun could have exploded seven and a half minutes ago and we’d have no idea! Enjoy the next 30 seconds of your life.

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

#110

Post by botverse »

I’ve been thinking about how to teach the size and proportions of the solar system to my kids, I’ve bought a couple of packs of blank RFID cards on which I intend to paint the planets over a starred background. And then walk with my kids the meters necessary to cover the distances before displaying them. What I don’t know is if there is a clever way to use the RFID tech, this website kinda offers an idea.
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