[elliottkember]

Objects not to scale. Not even close, and no mention of it (that I saw).

Graphing scale honestly is extremely important. A lot of people are convinced our sky is full of satellites because of visualizations like this.

[didgetmaster]

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.

[lukan]

"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."

Yes. And therefore a very valuable visualisation of reality.

Visualisations at scale are nice and useful, too, but they are misleading if the actual sizes are never shown to the target audience.

[sebzim4500]

Do you think that some people look at this visualisation and leave with the impression that there are city sized satellites flying above them?

[alias_neo]

> 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.

[brazzy]

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.

[XzAeRosho]

Absolutely. Common sense and critical thinking is less common than you may think.

[MarcelOlsz]

Yeah but I caught myself 3 seconds later.

[renewiltord]

Enough HN users are retarded enough that they'll start talking about Kessler syndrome because they don't understand what they're looking at.

[jihadjihad]

My dude, some people look up at the sky and see airplane contrails and clouds and conclude all sorts of outlandish nonsense.

[jillesvangurp]

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.

[schiffern]

"Floating around" isn't accurate. "Screaming around at 8 kilometers per second" is more accurate.

The fact that debris objects swee through an enormous volume of space per year (and are up there for years to centuries) makes it much worse.

https://commons.wikimedia.org/wiki/File:Orbital_Debris_Lifet...

http://www.youtube.com/watch?v=RvZ3Lr-Tj6A

[dhosek]

Proper scale makes the visualization impractical. I wrote about this with respect to a US map showing mountains on my mailing list: https://dahosek.substack.com/p/one-million-stories

“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.”

[SeriousM]

That would also mean that whenever I see a flat geo image, it could be a heightmap from a creator that was just too honest about scale.

[officehero]

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.

[NedF]

> Proper scale makes the visualization impractical.

So lie?

You can see from the comments most Hacker News users can't handle the abstraction.

Your blog post is great, but most people don't know the Earth is a perfect sphere or simple things like the sun is white, the real "Don't Look Up"

Universities have become pop culture, they are Gravity (2013), not 'science', whatever that word means now.

We cross mountains so that abstraction has a use, here it is for the nihilist crowd.

[varenc]

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.

[schiffern]

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.

---

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]

Sources:

[0] What really matters is altitude as this graph shows: https://commons.wikimedia.org/wiki/File:Orbital_Debris_Lifet...

[1] https://news.ycombinator.com/item?id=33210261

[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

[3] https://www.orbitaldebris.jsc.nasa.gov/quarterly-news/

[cantalopes]

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"

[JumpCrisscross]

> 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.)

[philipwhiuk]

That's true but not because the objects are massive. It's because they fly very fast and there's limited traffic management.

We risk solving the wrong problem due to bad visualisations of the situation.

[orbital-decay]

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.

[esjeon]

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.

[maybewhenthesun]

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