If the moon were only 1 pixel: A tediously accurate solar system model (2014)
224 comments
·June 13, 2025amelius
johnnyjeans
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. It becomes much more apparent how alive plants are when we observe them in a time-lapse. Now realize that plants are still relatively short-lived. The absolute oldest ones only go back to the early neolithic, that's only 14000 years or so. 1000 years is a long time for humans, but probably not for the trees where a single one can live 10x that.
From the hypothetical perspective of a star, with a lifespan measured in billions upon billions of years, the entire ecoscape of the world changes in a blink. From the sun's perspective, MENA was green just a very short while ago. Hell, Pangea wasn't that long ago. At this timescale, continental drift would be as apparent as the movement of boats are to humans. Anything that's working at the cosmic scale where the seemingly low speed of light sounds exhausting is most definitely working at this stellar perspective at the minimum. 14000 years of travel might as well be the equivalent of a 10 minute commute to the store.
Philosophically speaking, of course.
davidee
Thanks for this.
In addition to the insight, it reminded me to water a plant at a desk I no longer use. The plant's been with me through quite a bit and I have been neglecting it recently as I no longer see it regularly.
nilamo
Move your plant friend to your new desk?
mjcohen
For very philosophical writings about this, read "Last and First Men" and "Star Maker" by Olaf Stapledon. Written in the 1930's, these describe on a very expansive scale the history of, respectively, humanity and the universe. Very mind bending.
eddd-ddde
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.
M95D
We have a long way to go before we learn to move a star (or a rosette).
IAmBroom
Dude, pass the duchy.
chistev
Comments like this are part of the reasons I come here.
ifa_
yeah light _is_ actually pretty slow and we hit that in networking and optics pretty often if iirc.
like not even on a human level, universally even on a grand scale the speed of light is almost torturously slow, there’s nothing philosophical about it
lenkite
Might have been a deliberate rule enforced on the universe to avoid interstellar wars between sapient civilizations.
procgen
something can only be "slow" relative to something else. it's not an intrinsic property.
mr_toad
> Is light slow?
It’s always faster than you or I. Even if we zipped around at relativistic speeds it would still appear the same.
swyx
humans are a blip. i think the overwhelming scenario is we were a bootloading sequence for silico sapiens.
the_af
> Is light slow? Or is the human perception of time just scaled down as a result of our rapid metabolism and infinitesimality?
It's slow for humans to explore the cosmos.
"Slow" is meaningless without a frame of reference, and "humans" seems like a good frame of reference, since it's us -- and not plants or stars -- who are writing on HN to discuss this.
Because it's us, humans discussing this in HN, the frame of reference is implied and it's not necessary to spell it out.
lisper
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 matter.
wafflemaker
Don't forget gravity drive. No more Gs. And the same technology would give us real artificial gravity, not this nauseous rotation artificial gravity.
dyauspitr
You can accelerate continuously at a comfortable 1g and get to 0.5c in about 5 months. G forces are not the issue.
lisper
The Lorentz factor at 0.5 c is 0.86 so this only reduces your proper travel time by about 15%. Even at 0.9c the LF is only 0.43, so it would still take you 2 years just to get to Proxima Centauri. And as you approach c, 1G acceleration speeds you less and less. And you also have to slow down at your destination.
munksbeer
> 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.
raxxorraxor
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 minutes from the surface of the sun to us. Or about 100000 years from the center of the sun to its surface.
causal
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.
nilamo
> 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.
amne
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.
danudey
It depends on acceleration though. If acceleration and deceleration take long enough, it could take an entire generation to get up to a fast enough speed that relativistic effects make any difference, and another generation to slow down enough to interact with anything you might see.
Plus if you're traveling at near light speed, running into any matter at all would be pretty devastating for whatever craft you're in.
Edit: someone further down claimed that the math says that accelerating at 1G would get you to 0.1c in a month, so that's actually not that bad all in all. I still maintain that hitting any matter at those speeds might be unpleasant.
thombat
But unless you have a way of slowing down again you'll never see anything of your destination, just the briefest of flares of light as you sail past. And if you do have a way that involves anything like physics that we recognise, you've brought along a huge rest mass that then got accelerated to near light speed. Probably your civilization needs to be approaching Kardashev Level 2 to pull this off.
eslaught
One thing I've always wondered is what fraction of c is actually realistically achievable with current technologies? (Maybe with scenarios for manned/unmanned spacecraft.)
Like are we at 0.1% or 0.01% or more orders of magnitude off?
chrisweekly
> "A photon instantly travels to the end of time"
Please explain this. TIA
mock-possum
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.
sheepscreek
It’s not the destination, it’s the journey :)
ant6n
10,000 years of empty space to get to the next solar system. Exciting.
once_inc
Assuming our models of the universe are correct, and faster than light travel is impossible. There are very strong reasons to believe this, but perhaps we can cheat by stretching and compressing space around us.
gwbas1c
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?
mr_toad
> It makes me wonder what kind of "life" could perform interstellar travel?
That’s essentially the premise of Project Hail Mary. Good book.
EB-Barrington
[dead]
nurettin
Meh, most of it is just more of the same thing. I'd rather play with a paper plane than float in space.
beklein
Maybe light’s insanely fast and space is just huge. It’s all relative ;)
isolli
I would say they're two sides of the same coin. The time it takes for light to travel the universe (which makes communication even with nearby stars essentially impossible) is what makes the universe huge.
neuroelectron
Luckily FTL communication isn't actually impossible and special relativity only applies to energy and mass.
mr_toad
> I think we'll have a holodeck before we reach another star. And maybe that'll be enough.
I agree, but not because of the relative difficulty of the technology, but because we spend way more on entertainment than space exploration.
uncircle
True but doesn’t matter how slow light is. The closest to c your speed is, the shortest the time you experience on board of the space ship. At light speed, space and time cease to exist. You reach destination instantly.
So the goal is to create engines that can take us close to light speed. Then the issue is braking (spacetime expands as you slow down…)
baxtr
Me scrolling is faster than the speed of light!
Nice.
schaefer
Dude, chill.
We’ve got to preserve causality. :P
clocker
> Lightly is incredibly slow
Its relative! Sitting on a couch and watching the pixel move from the sun to the earth for 8 minutes feels incredibly slow but if you are actually traveling in a light speed aircraft then it won’t feel that slow.
orobus
If you were actually traveling at the speed of light it wouldn't feel like anything at all! Photons don't 'experience' time—any length trip would be instantaneous from the traveler's point of view.
quchen
Quite the opposite, much like when skydiving, going really fast without any close reference point makes everything stand still. And in space, there wouldn’t even be (very loud) atmospheric drag to physically remind you about what speed you’re actually going.
jjbinx007
I believe the OP was referring to relativity - the closer to the speed of light you get the slower time appears to tick. So if you could travel at light speed you'd arrive at your destination immediately from your reference frame, but much slower from another person's.
amiga386
I love how simple the HTML/CSS is. Absolute positioning with really large left: values.
#saturn {
position: absolute;
left: 412397px;
height: 34px;
width: 65px;
fill: #ffa043;
}neuroelectron
Caused Brave in iOS to crash. I have a newer iPad mini with 12GB ram too. But luckily It didn't crash until I tried to close the tab.
pc86
This seems like a browser issue more than anything else. Yes it's "weird" to have millions of pixels horizontally on a page that is only a few thousand pixels tall, but it seems like an absolutely reasonable edge case that the browser should support.
zhengyi13
I feel there's a joke here about "edge" cases from scrolling ridiculously long horizontal distances, but I'm not smart enough to make it.
Sharlin
“Why not save space by storing dimensions as uint16 internally?”
Zardoz84
Huge values could rise problems on IE (if someone keep using it and supporting it)
2OEH8eoCRo0
We have come full circle. I'd imagine that px uses a surprising amount of abstraction.
computator
Given the great distances and how small the planets seem at that scale, I'm surprised that we can see any of the planets with the naked eye. Thinking about Jupiter, it's 140K km in diameter and about 629M km from Earth. That's a ratio of 1:4500. So imagine a U.S. dime that is 1.8cm in diameter placed 1.8 x 4500 = 8100 cm away. Would you be able to see a dime that it 81m or 266ft away at nighttime, assuming it slightly illuminated? We can see Jupiter, so I guess we should be able to see the illuminated dime too.
dang
Related. Others?
If the moon were only 1 pixel - https://news.ycombinator.com/item?id=39686916 - March 2024 (1 comment)
If the Moon Were Only 1 Pixel (2014) - https://news.ycombinator.com/item?id=32936581 - Sept 2022 (108 comments)
If the Moon Were Only 1 Pixel (2014) - https://news.ycombinator.com/item?id=27573172 - June 2021 (69 comments)
If the Moon Were Only 1 Pixel (2014) - https://news.ycombinator.com/item?id=21735528 - Dec 2019 (82 comments)
If the Moon Were Only 1 Pixel – A tediously accurate map of the solar system - https://news.ycombinator.com/item?id=13790954 - March 2017 (81 comments)
If the Moon Were Only 1 Pixel – A tediously accurate map of the solar system - https://news.ycombinator.com/item?id=13217129 - Dec 2016 (11 comments)
If the Moon Was Only 1 Pixel - https://news.ycombinator.com/item?id=12038584 - July 2016 (4 comments)
A Ridiculously large accurate scale model of the Solar System - https://news.ycombinator.com/item?id=10330303 - Oct 2015 (1 comment)
If the moon were only 1 pixel: a scale model of the solar system - https://news.ycombinator.com/item?id=7551423 - April 2014 (17 comments)
If The Moon Was Only 1 Pixel - https://news.ycombinator.com/item?id=7341690 - March 2014 (178 comments)
technothrasher
I remember back in elementary school, way before we had such things on computer, we had a vinyl roll for the age of the planet. You'd roll it out in the hallway, starting with present day and watch as the different time periods came into view. You were just a few feet at the origin of man, at the end of the hallway by the time you got to the beginning of Cambrian era, and out the door and across the huge athletic field before you got to the formation of the planet.
tomxor
Shameless plug: Accurate solar system in 192 Bytes:
https://www.dwitter.net/d/26521
The red bit is the sun. 1000 kilometers per pixel, and 1000 seconds per second.
They all fit onto the screen by looking through the orbital plane, as if through a telescope from a distant world, i.e effectively an orthographic projection. The orbits are accurate in terms of mean orbital distance (in reality there is slight perturbance) and sidereal periods.
darajava
Incredible - how does this work?
tomxor
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)
Surprisingly the precision used in those encoded values is enough at 1000km per pixel (I checked).
ByThyGrace
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.")
andersco
Still an extraordinary experience after all these years and possibly the best use of horizontal scrolling I’ve seen. Lots of previous discussions and posts on HN: https://hn.algolia.com/?q=if+moon+only+1+pixel
IggleSniggle
It's very very good! I thought this one hit hard though, I assume inspired by the moon = 1-pixel viz.
arrowsmith
This is great, but it needs an update: wealth inequality is even higher today than it was when that site was created.
E.g. it gives Jeff Bezos's net worth as $139 billion, but today it's $228 billion.
zurfer
that's a great share, I feel like it would also benefit from setting the "speed of light", as something like median average yearly income.
athenot
On the same note: https://xkcd.com/980/ (from 2011 when Bezos "only" had $18b)
susam
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 proper orbits at scale using perspective projection, I'd only be able to render one planet large enough to be visually interesting. The rest would appear as small dots. I didn't want to use an orthographic projection, as it wouldn't reflect how we actually see the universe.
Those were, of course, limitations of a still image. An interactive page like the one in the original post does a fantastic job of conveying the vast scale of our solar system, both in terms of the sizes of the planets and the immense distances between them.
dahart
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.
dahart
I tried it, including Pluto, and it works fine. Shading is quantized at Pluto but the spheres are all round.
jethkl
There are many physical scale models of the solar system around the world, many walkable, some bikeable: https://en.wikipedia.org/wiki/Solar_System_model
I've seen several, Planet Trek in Wisconsin is a good bikeable one with high quality signage. The sun is downtown, the moon is the size of a peach pit, Pluto is ~20 miles away.
idlewords
And for the lazy, there's the 1:1 scale model under your feet.
robin_reala
The light speed toggle really hammers home the emptiness. Like, I know that the Earth is ~8 light minutes out, but sitting and waiting 8 minutes for a few pixels to appear when scrolling away from the sun…
jstummbillig
and even this is not making it super tangible, because the speed of light to monkey brains is basically infinite.
CapsAdmin
I've seen countless analogies that explain the size of space, but this was really something else. Especially how frustratingly slow the speed of light felt.
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)
socalgal2
Not the same but related? Powers of 10 by Eames
https://www.youtube.com/watch?v=0fKBhvDjuy0
Interestingly, that Hawking visualization makes all the same affordances mentioned in the 1 pixel visualization. They show the earth and moon to scale, then the video shows an aerial view with all the planets much too large. Jupiter is 2x the size of the sun. Saturn and its rings 2x that.
Kuyawa
I've always used this aprox dimensions:
Sun diam 1,400,000 km
Eth diam 13,000 km
Sun dist 150,000,000 km
Mon diam 3,500 km
Mon dist 300,000 km
Simply put, imagine a yellow beach ball the size of a washing machine located a block and a half away from your house, a blue marble being the earth on one side of your keyboard and a peanut being the moon on the other side
Kuyawa
Now, using the basketball 24cm (earth) and tennis ball 6.5cm (moon) comparison, they would be separated by 7m in your living room and the sun would be 13m tall (a cherry tree) located at 3km from your house
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.