Scale distortion is very practical when differences are either miniscule or astronomical. A poster of our solar system where the sun and planets are at scale would look like a black piece of paper with a tiny white dot in the center.
From what I remember there are various different depictions for different purposes. Most are just showing order and what they look like visually so the precise scale is a detriment and skipped. Most of the solar system to scale things I've seen in person are multiple blocks long so the planets are a reasonable size, there's not really a reasonable way to print a to scale in both size and distance in a book.
If you're being accurate in both distance and size scales your smallest dot would be Mercury and the distance from the Sun to Neptune (assuming this is a modern text book and we're dropping Pluto) would be 922000 of those dots. Even if we print it at the higher 1200 PPI [0] used for line art that's ~770 inches, that's a huge image far larger than any reasonable book. You could do it with a fold out but that's it's own expense and unreasonable for inclusion in an actual textbook.
That's why I was saying doing both accurate size and distance is difficult for the solar system.
[0] Images are more often printed at 300 PPI but I'm giving you the best case scenario here.
> that there are city sized satellites flying above them
I don't think this is so much the issue, as much as that I didn't think about it.
I opened it and my first thought was wow, it's packed up there. Didn't consider the size of the things it's displaying relative to things on the surface.
There is certainly some merit in ensuring that first impression is accurate.
> I opened it and my first thought was wow, it's packed up there
I mean, it is also pretty packed up there. Considering that a rocket launch has to give every object up there a decently wide berth, it's still a shit ton of moving obstacles that have to be constantly taken into account - the relative size of the gaps between them doesn't really change that equation much.
Yes. I once overheard a flat earther argue that spare reporting is fake because there are supposed to be tens of thousands of satellites, yet photos from the ISS don't show any of them.
It's less illusion and fantasy and more code for "what I think." If you notice, it's only uttered by people who believe their own reasoning should be automatically accepted as truth. Ego leaves no room for doubt or embarrassment.
Yep, it looks much more dramatic than that is. A realistic scale would make objects invisible, unfortunately. So I can see why they make things bigger than they are.
The reason why there are so few incidents is that low earth orbit is simply a very large volume of space. It would be a mistake to think of it in 2D terms, it's a few hundred km in height and it has an area even at the lowest orbit that is larger than the surface of the earth. The total volume is orders of magnitudes larger than all our oceans combined.
So what's the chance of 2 out of a few hundred thousand things floating around in random orbits crashing into each other? It's not zero. But it's close enough to zero that it's very rare. But high enough that people worry about it somewhat. Obviously some orbits are quite congested and having a lot of debris scattering all over the place after a collision makes things worse. And the speeds at which things are moving around would cause some high energy collisions even for small objects.
“any accurate depiction of elevation would be indistinguishable from a flat map at that scale. The coast-to-coast measure of the US is a bit under 3000 miles, while the highest elevation in the continental US is a bit under 4½ miles above sea level, so in a 1000-pixel map, that would translate to a 1–2 pixel height for Mt Whitney which is the highest point in the contiguous United States.”
and also
“the difference in elevation between Everest and the Marianas Trench is less than the bulging of the earth from its rotation. And that amount is less than you might guess. If we scale the earth down to a diameter of one foot (which would be bigger than my childhood globe), the bulge would be 0.04in or roughly 1mm. Good luck distinguishing your oblate spheroid from a sphere with those numbers.”
Yes and to be clear on what "practical" means here. If there's a mountain between origin-destination for a road trip it's relevant to highlight it. In the case of orbits the objects may be small but they're very fast and very dangerous.
I think calling them dangerous is even a bit misleading as they're well tracked. Some of them even autonomously precisely position themselves rather than be on ballistic trajectory.
Only the largest objects are trackable. Objects in the 1-10 cm range are large enough to destroy satellites instantly but too small to track. Obviously any visualization will only show known objects.
This explains both why "dangerous" is accurate, and why autonomous avoidance based on tracked objects (ala Starlink) is 'necessary but not sufficient.'
An honest visualization to scale would just have the satellites being faint dust smaller than your pixels? Wouldn't be useful. But agreed that if you could zoom in and visualize the actual scale that'd be interesting and informative. Would be cool seeing the difference in satellite size. But would be less useful as a broader visualization of LEO.
Objects are not to scale for unavoidable reasons, but time is also not to scale. These two effects tend to cancel out.
People look at this visualization for what, 60 seconds? But the issue is that objects are zooming around up there for years-to-centuries.[0] The total volume of space swept out is massive.
Invariably the "not to scale" comments always get pointed out every time this is posted, but the temporal distortion (which makes people underestimate collisions) is never mentioned. Unless I mention it[1] of course... ;)
There's a much much better educational ESA video[2] which addresses some of the misconceptions in this thread, found via (of all places) Don Kessler's personal website.
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If you want an expert perspective on orbital debris (vs..... whatever these HN threads always turn into :D ) I highly recommend you check out NASA Johnson's Orbital Debris Quarterly.[3]
[2] As this video points out, collisions scale as density squared, which is why all major collisions have happened near 80 degrees latitude: http://www.youtube.com/watch?v=RvZ3Lr-Tj6A
Actually the Kesler syndrome, a space debriss cascade is a very real threat and a real concern. I suggest an interview with the commander of the space control quadron in a radiolab episode "Little Big Questions"
> the Kesler syndrome, a space debriss cascade is a very real threat and a real concern
It’s also widely misunderstood.
The risk is in trashing specific orbits. Below 600 km, that would mean certain orbits are too polluted to use for a few months to years. (A dense, compact object above 600 km could stay lofted for decades to over a century. But again, only within a predictable volume.)
It's actually mostly because we allow objects to fly too high. Small height differences have a huge difference in orbital lifetime (and therefore risk).
Some kind of a relative velocity at the closest approach or a collision probability overlay would be way more useful to have than proper scale. That would make it immediately clear that lazy well-kept orbits like GEO are much safer than e.g. 567km SSO at the poles. Or some color coding for the apparent magnitude.
While I totally agree with the logic, this particular visualization might mislead unsuspecting viewers into believing that our LEO is almost fully saturated. In reality, the satellites are so small that they would miss each other even if placed on the same orbit.
A true-to-scale visualization would however be entirely misleading for everyone since it would be completely empty. Just look up in the sky at a clear sky. You would hardly see a single satelite and a visualization on a computer screen would show even less due to pixel size.
well... Out sky is full of satellites.
Granted, there's a lot of empty space in between. But ask any (hobby) astronomer and they'll start a rant about starlink :-P
> discover that everything I've coded is unnecessary and there is an easier way to achieve the same goal
In my experience, there is no good shortcut to this realization. Doing it wrong first is part of the journey. You might as well enjoy the necessary mistakes along the way. The third time’s the charm!
Correct. The car industry intentionally socially engineered the US to associate the giant individual and social burden of car ownership with freedom. A great documentary called Century of the Self covers this and other related things ( https://www.youtube.com/watch?v=eJ3RzGoQC4s )
Man, my parents are such fools. Driving me to school, to putt-putt, ice cream. Then, off to work in their car just to make a payment and buy gas and cover my college tuition. The doctoral thesis of my post capitalism art history professor proves they were scammed by their capitalist overlords.
Moving to the US, the traffic light system was a big culture shock for me. No major/minor dendritic road system laid out like a tree like I was used to — more like right angles everywhere and so many delays. Traffic lights on every single intersection. So inefficient.
And when you mention it, a surprising number of people say “that would never work here. People don’t know how to drive”. So little faith!
It vibrates and tries to gently guide you. It will absolutely not overpower you if you are swerving in an emergency. You are talking hypothetical nonsense.
> Adjectives in English absolutely have to be in this order: opinion-size-age-shape-colour-origin-material-purpose Noun. So you can have a lovely little old rectangular green French silver whittling knife. But if you mess with that word order in the slightest you’ll sound like a maniac. It’s an odd thing that every English speaker uses that list, but almost none of us could write it out.
Foreign languages always sound strange. There are rules that are invisible even to the native speakers who know them. The romance is not in knowing them, but the fun of figuring them out.
The comment asking about riding positions drop bars was hilarious.
Lots of Americans in the comments is probably why, plus the Hacker News tendency toward armchair expertise.
The American grid system tends to produce hills that are unmanageable on a town or cargo bike, so bicycles are a fitness/enthusiast thing. And US cities are much more spread out, too. In more walkable European cities, these bikes make a lot of sense.
There are so many excuses for why Americans don't ride. I have not heard about the grid system making the hills too steep before, but I suppose it applies to San Francisco, so I concede that could be a legitimate excuse. I went to SF with a heavily laden tourer bike and I found the hills manageable as you get a breather at the stop lights. I made good progress despite the hills. I might have only had 40kgs of cargo, but I did get an idea of the challenges.
There is much to criticise but there is so much to like. The sprawl of US cities was not a problem for me, it was a lot easier and less stressful on US roads than what we get in the UK. The shoulders on most US roads are defacto cycle lanes, which I really liked since a good speed could be maintained.
As a British observer, I can't help but laugh at how everything in the US is bigger. I do my grocery shopping by bicycle and I am the only person in the supermarket carrying 30kgs of stuff up a very steep hill. Everyone else drives. My bike is a normal one, but I feel that, if I was American, then I would be compelled to have some special needs bike, either a cargo bike or electric, to 'haul' even more stuff.
Everything just has to be bigger!!!
The book of excuses for not cycling is massive in America, but, I have never been to a better place for utility cycling. The whole place is really well set up for utility cycling, you just have to see it that way.
Fitness cycling is a high status pursuit, much like those silly games like tennis that were invented just to show how high status you are. Golf is the classic, so much arable land not under the plough is a true flex of wealth.
Fitness cycling shows that you are not working class, that you have the resources to not work. Utility cycling is low status, it shows you can't afford a car or you have been banned.
With utility cycling there is always a reason for the ride, it is not out of choice, if you don't do the ride, there will be consequences such as not having a job or having no food in. Yet there was a time before the car when all cycling was for utility reasons.
These would work beautifully in Dutch cities, although you can easily see from the design that its native biotope is Paris, where cars are increasingly being pushed out of the narrow streets.
The discussion is very much a case of people from the USA having the far too rare realisation than most places in Europe have nothing in common with their country.
Are you sure? From the major EU cities I have visited at least 2 which have many "hills that are unmanageable on a town or cargo bike" (Zürich & Lisbon). And if we include smaller places its many many more places.
Now what "unmanageable" means can differ quite a lot by person. Like some people would call some of the streets in Lisbon "unmanageable" by walking ;)
But then in both cases it only affects part of the city and throw in a E-Bike and thinks are often quite fine.
Anyway the point is, the bike from the article seems quite far away from a general purpose cargo bike. But for places where it fit its niche it probably shines.
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