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I don't really know what I'm looking at here, but it feels very sci-fi and I'm into it.

I also wonder, how do they track so many objects? Who actually tracks them? How much does it cost (energy, engineers) to maintain the tracking systems?

Edit: Are these all simulated orbits? Is there a big "orbit registry" somewhere? And what are the "beams"?

LEOlabs operates its own radar systems that point upwards-ish. The "beams" you see are the fields of view of their radars. When an object crosses that field of view going at orbital speeds, LEOlabs tracks it and uses the partial trajectory information to figure out the orbit of the object. From there, it can potentially associate that object with existing objects in its own and other databases (the US Space Force, which operates its own radars, is one of the best-known).

It then sells that information to spacecraft operators, who may be using the orbital information to determine if their spacecraft has a risk of hitting another object in space, or to figure out where their spacecraft are in the first place (usually when they're not talking to the ground).

I am pretty certain they must be dead reckoning the location with occasional updates.
That's how all space debris tracking works. Luckily orbits are rather predictable paths, but there's still atmospheric drag, lunar and solar gravity, non-uniform Earth gravity, solar photon pressure and measurement imprecision to deal with.
Is there a big orbit registry somewhere? Yes. https://www.unoosa.org/oosa/osoindex/search-ng.jspx Each individual object is observed every few weeks, and then they estimate its current position with math and physics.

How do they track them? With big expensive radar systems, mostly paid for by the military. It's an international collaboration. https://en.wikipedia.org/wiki/Space_domain_awareness#Systems

LEOlabs operates and pays for their own radars. They're a commercial company.
The US Air Force, for one, is responsible for tracking everything it sees. That generally means computing TLAs for each object. Whether they release this info, I don't know.
I’ve played kerbal space program for over 500 hours and I can confirm LEO looks like this in my game.
That's impressive but is your processor alright? PS4 Pro nearly catches fire trying to simulate one modular space station.

Do you know if there's been any news on KSP2? At this point I'm not sure it will ever happen.

Neat. I wonder if this is solely generated from their array of distrbuted sensors, or if this is just another visualization tool using space-track.org's data.
Im on my phone but you could probably look in the network requests panel of your browsers developer tools to see if any request is sent to space-track.org.

Side note: does anyone know of a good tool / app for looking at things like that on iOS ?

No network activity. Seems like it might update occasionally.
space-track has pretty aggressive rate limiting, so they'd probably download the catalog to their servers once a day or so and work off of that.
It doesn't appear to include any objects in the GEO belt (which space-track does), so I'd guess it's just objects from LEOlabs's own sensors.
The fact that I can view LEO objects in real-time on a phone just shows how awesome technology has become.

Even 10 years ago, that thought would have been ludicrous.

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That crashed my browser HARD. Needed a full reboot. Thanks for that!
Just curious ;-) Whom are you thanking in particular? The web page authors? The browser programmers? The OS programmers? Perhaps the graphics driver programmers? HN? The OP? The readers of your comment?
Whoever is at fault. They are just putting the thanks out there. It is not their fault that those responsible have not equipped themselves with the proper receivers.

It's like a bad API. The docs say to send, but there's no mechanism to receive. It's not the fault of the user.

Yeah, there's a lot of objects being rendered on screen. My GPU (3090 Ti) was running at about 41% while I was playing with the site. Amazing site, but definitely GPU intensive.
My GPU - an Intel 4600 integrated GPU in a 2014 laptop - kicked up to about 95% utilization while playing with the site. I suspect I was getting fewer details than you - mine was not silky smooth but still perfectly usable, at what I'd estimate to be about 20 FPS.

That your powerful GPU was putting in some effort while my poky GPU [edit: and my 2018 low-end Android phone, admittedly at ~4FPS] are still able to render the scene at all indicates to me that they put in some impressive effort to make the graphics scale for different configurations!

This Safari tab is at 65% GPU utilization on M1 MBP. Can't quite tell what frame rate but appears visually silky smooth so guessing 60+.
Do you have a high refresh rate monitor? I only hit ~35% GPU usage with 1660ti but my browser is synced to 60 FPS.
It is 100Hz refresh rate - so 100fps I imagine.
Which browser are you using? WebGL2 should be perfectly safe. The tab crashed for me once but Firefox just reloaded it without a hitch.
These kinds of visualizations give you the impression that LEO is much more crowded than it actually is.
I feel like the "objects" aren't anywhere near being to scale. Pretty sure they should be MUCH MUCH smaller relative to the earth to be realistic.
If they were, we wouldn't be able to see it in visualizations.
I mean, you need to actually be able to see the objects for it to be a visualization though. If the satellites were drawn to scale they'd be smaller than a pixel.

I think you can get a decent sense of how crowded (or not) an area is by watching how many objects pass though it. The state that I live in looks like it has somewhere between 1 and 10 satellites above it at any given time, which drives home the point that LEO isn't quite as "busy" as it feels from a zoomed-out, sped-up view of the map.

There's another comment saying that the ISS to scale at the default zoom would be roughly 1/150th of a pixel. It stands to reason that every satellite here is much, much smaller than that.
Right, because apart from the moon, all objects orbiting the earth are considerably smaller than the New York Metropolitan Area which would not be your understanding if you took the visualization to be a scale representation.
This looks extremely crowded - but reminds me of how apparently hard it was to find or bump into another ship crossing even a confined sea like the Med before sonar. With three dimensions here and more avoidance planning, even this level of space probably looks very empty still.
It is of course not to scale. You simply couldn't see any satellites unless looking at ridiculously small areas. Most of them measure a few meters at best.
This is fascinating. Can someone point me to resources that explain Starlink's seemingly (but obviously not) random trajectories as well as their positions (some in a line, some on individual trajectories).
The ones all in a line are recently launched. They are launched ~50 at a time into a low orbit and use thrusters to raise themselves up over the course of a few weeks or months. During that process they are all lined up in a row which slowly lengthens over time. As they reach operational altitude they separate into groups and each group spaces itself evenly around one orbit for even coverage.

For more detail than you ever wanted, check here: https://mikepuchol.com/modeling-starlink-capacity-843b2387f5...

Thanks! Macroexpanded:

LeoLabs: Low Earth Orbit Visualization - https://news.ycombinator.com/item?id=31413373 - May 2022 (3 comments)

LeoLabs: low earth orbit visualization - https://news.ycombinator.com/item?id=31180865 - April 2022 (1 comment)

Low Earth Orbit Visualization - https://news.ycombinator.com/item?id=26309367 - March 2021 (93 comments)

Monitoring a high risk conjunction between two large defunct objects in LEO - https://news.ycombinator.com/item?id=24773462 - Oct 2020 (150 comments)

Low Earth Orbit Visualization - https://news.ycombinator.com/item?id=22165645 - Jan 2020 (1 comment)

That's really cool. I know this comment is low-effort, but I don't really care - this type of real-time visualization is really interesting and I want to see more of this sort of thing going forward.

That said, the blue dots are "unknown" - what could those possibly be? Not trying to be conspiratorial or anything, but is it some sort of debris from classified operations or foreign intelligence operations?

Often you can figure out what spacecraft/rocket a piece of debris came from with a good catalogue of orbits and some math - these are labeled "Debris." Often you just can't - these are labeled "Unknown."

The US Space Force does a lot of the object cataloging, and they occasionally will pretend one of their classified satellites doesn't exist, but there's only a handful of these.

> but there's only a handful of these.

Huge if true.

Oh, there are plenty of US satellites with classified payloads/missions; I just mean that most classified US satellites DO have orbital elements listed in the Space Force catalog.
Often not in the public catalog though.
I'd add that it would be pointless to try to hide a fair number of them, given that they approach the size of school buses (no joke — the now-retired KH-9 was nicknamed "Big Bird" for good reason) and can be imaged on relatively consumer-ready optics. Some Russians made a nice stink a few years ago by using (IIRC) laser illumination to make some relatively high-res shots of American recce sats.

The interesting aspects of them have to do with how far off-axis they can function. This was the major consequence of loss of the Morison leak of the KH-11 shots of a Soviet carrier to Jane's Defense Weekly — the image revealed how far off-axis it could image and some clues to how it processed imagery.

I only saw one blue dot while looking around (briefly on a laggy computer, so there are probably plenty of others): "L6188942", which you can isolate in the view by searching for it. https://www.n2yo.com/database/?id=81078#results shows there are no results for the "NORAD ID" for that same object.

I don't have any domain knowledge here, so can't argue either way, but one possibility I can imagine is it's a place holder for "somebody launched something and we just don't have the records yet". No clue how realistic that is, and I'd trust my sibling comment's explanation more, but it wouldn't shock me if it takes time for info to propagate.

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If the earth is 750 pixels wide in the default zoom, each pixel is 10mi/16km. Scale image of the ISS would be roughly 1/150th of a pixel.
Thank you for this. While the visualization is useful/interesting, it frustrates me how often similar visuals are used in news stories about space junk. Yes, it's a problem, but using visuals like this without proper explanation misrepresents it terribly.
Yes, and they don't add footnotes. From visualization it looks like crash is inevitable. But yeah, otherwise there would be no visualization.

Think about it: they say 19334 objects are tracked. Imagine that many cars or trucks in the world scattered all across. Then extrude that to couple hundreds of kilometers. Would that feel congested to you? 19334 new cars are being manufactured in less than 2,5 hours...

And that's before you add oceans and horizontal planes...
We do love car analogies. I adore them myself. But you did forget one thing. On the surface, a typical car is averaging something like 35 mph. A low earth orbit satellite around 7.8 kilometers per second.

I otherwise totally agree with your point.

Those news stories would be a lot less interesting with a black picture of space with a footnote that the satellites are there, just too small to see.
With orbital junk visualizations, relative size isn't that important. What matters is collision probability. Low polar sun-synchronous orbits where the remote sensing stuff typically lives are super crowded, especially at the poles; in contrast, GSO is a well kept orbit with low relative velocities, and the dead stuff drifts away, so it's really safe.
I would love to see a visualization comparing orbital traffic/debris with marine traffic.
It would be nice to have a selector for the scale level of the satellites, perhaps x1000, x100, x10 and x1.
And perhaps a density map too.
They provide conjunctions as well. This is actually funded by DoD, they're not messing around.
I always try to explain it thusly: “up there” is “bigger” than “down here” because the radius is greater and there’s three-dimensional separation, and nobody “down here” is worried a few hundred thousand or even several hundred million busses might collide, so why worry about it “up there”?
This is really nice made and shows how crowded the LEO space is
Or _not_ crowded.

We have more boats and planes than there are orbital objects. If you open flightradar you'll see an absolute abomination of planes flying overhead. Yet, unless you live close to an airport, you probably won't see any. The planet is really large. Space is larger still.

Not sure why this is downvoted. Space is really, really big (the name fits!). The biggest Earth-orbiting satellites are a bit less than the size of a school bus (the biggest being something like KH-9 size) in terms of mass, somewhat bigger when it comes to things like parabolic dishes.

We worry about orbital debris because of the consequence of loss. There's a lot of room up there (not discounting everyone's concern).

Those long, straight-line convoys of Starlink satellites are fascinating. There's a few of them I could see scattered around the Earth. At what point do they start breaking up into unrelated orbits?

Looking forward to using this website to try spotting satellites at night. There's something strangely thrilling about seeing objects in the night sky that were placed there by people.

For spotting satellites at night, try my site: https://james.darpinian.com/satellites/

Most of the satellites shown on the Leolabs site are too dim to see without a telescope because they don't reflect enough light. My site calculates brightness and filters down to the ones that you can see with the unaided eye.

There are still quite a few! ISS in particular is very bright and can even be seen before sunset. The new Chinese space station Tiangong is also a good one to try. In the next few weeks it's expected that the recently launched BlueWalker-3 will become quite bright too as it expands its enormous phased array antenna (64 square meters!). But the coolest is probably if you can catch a recently launched Starlink train, 50 satellites all visible simultaneously or within seconds of each other. (A few weeks after launch the Starlink satellites are no longer visible as they reach their operational orbits.)

I have used your site to successfully spot Starlink trains and the ISS several times. It's very well-designed and the included street view overlay especially helps with knowing where in the sky to look.

Thank you!

Very nice! Thanks for sharing this--looking forward to using your website!
Your website is very well designed, thanks
This is really well done, I will try it out tonight!
Wow. I allowed Chrome to know my location for the first time and Street View was in my front door. I thought it was going to use the IP but it's impossible to be that accurate, does it Chrome use my Home on my profile location or something like that?
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The Street View cars log information about wifi access points, and use wifi data from your device to guess your location.
That'd explain the changes to Location Services on Android over the past several years.
Is it related to Android though? I read somewhere/thought that it is primarily the Google Maps cars recording WiFi data and not phones). Europe wouldn't be covered at all if it was coming from the phones, right? (GDPR)

I mean, you can have a street full of iPhones - which I assume is a regular occurrence in USA, where people trust Apple - and still Google Maps on iPhone would guess well enough where you are. For example, I'm far away from the street and Google hasn't passed here recently, so my WiFi-based location is always way off (using Android). In my other home (and vacation home in another country) it's the opposite, because the cars have passed quite recently.

The story checks out so far for me... but I am kinda lazy to search for the source on this right now, so pls share if you have it.

> Europe wouldn't be covered at all if it was coming from the phones, right? (GDPR)

Which part of GDPR would prevent Google from collecting pairs of (Wi-Fi BSSID, approx lat/lon), with the consent that you gave when you set up your Android phone, and using it for their own purpose without giving it to any third party?

They give it to a third party - other chrome users. I was once in a train, and location services located me in a suburb hundreds of km away - clearly I was traveling with someone living there, using a portable/mobile hotspot. These kind of edge cases are hard to prevent (and rare), but still can lead to serious fines.
Your example doesn't demonstrate Google giving the data to other Chrome users. Making decisions based on the data is not the same as giving the data out.
I believe this data mainly comes from phones, not street view cars. There are about a million times more phones out there than street view cars, and they all have GPS and Wifi. Apple had this feature long before Apple Maps was a thing, and they didn't license Street View data from Google.
When you enable location, Chrome will send some pieces of information about your computer to Google Location Services to get your GPS location. Then Chrome sends that GPS location to the site you're visiting. Using information from your profile wouldn't be accurate if you were e.g. at a coffee shop.

>The information that Chrome sends to Google Location Services may include:

>The Wi-Fi routers closest to you

>Cell IDs of the cell towers closest to you

>The strength of your Wi-Fi or cell signal

>The IP address that is currently assigned to your device

https://www.google.com/chrome/privacy/

Disclosure: I work at Google but not on anything related to this.

This sounds like I work for Schutzstaffel but just doing paperwork for them
I put the "not on anything related to this" part in to clarify that although I'm speaking about Google and work at Google, I'm not really a firsthand source, I'm just providing thirdhand information.
I can't tell if the times are for my timezone?
Times are displayed in the time zone your device's clock is set to. Unless you use the "Change Location" feature, in which case local time zone of the selected location will be used, with explicit time zone abbreviations shown.
Thanks for your site! I used it with my kids during COVID lockdown to watch the ISS and other satellites. It’s great
Forced to keep eyes at the floor (for your own good, of course)
This site is great and is one of my favorites. I occasionally check it and set an alarm on my phone. I will announce to the people that I am with "satellites passing in 3 minutes", run outside and impress people. Great fun. Thank you, thank you, thank you!
The nightmode streetview is very cool.
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That’s awesome. We have a few upcoming for the southern hemisphere. Excited to see them!
I just watched Tiangong space station with my bare eyes. Beautiful. Looking forward to watch 14 starlink satellites tomorrow. Thank you so much for your website.
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I love you saw a train a while back because of your site
Hey just want to say thanks a ton for making this. My son and I went out side and laid on the patio watching the starlink sats pass by and it was neat. We never realized that they were there.
> At what point do they start breaking up into unrelated orbits?

I can't speak with any authority, but in general a train of satellites would likely be moving in an orbit with either the apogee/perigee similar to the target orbits, but the other end of the orbit being higher or lower. Each time the train reaches the extremum at the target altitude, one of the satellites thrusts to adjust the other side of its orbit to target, which pushes it out of the pack.

The specifics may be so different as to make that explanation totally wrong but it's probably not too far from the general principle.

> At what point do they start breaking up into unrelated orbits?

It's not as easy to see as in this visualization, but Jonathan McDowell (https://twitter.com/planet4589) posts graphs on his website of each launch of starlink satellites as they raise orbits. https://planet4589.org/space/stats/star/starstats.html

Scroll down to the individual launches and there's images you can click on of the orbit raising progress of each launch.

Example of the Starlink 4-21 mission that launched on July 7th of this year: https://planet4589.org/space/stats/star/spl51.jpg (One satellite failed, which isn't that unusual, and will de-orbit probably sometime early next year if they don't recover it.)

And the adjacent graphs show phase (line growing longer, spreading along an orbit), and plane (line breaking into multiple lines slotting into nearby orbits). Positioning is accomplished by spending time at different-than-deployed altitudes, mostly lower. Lower gives a difference in nodal precession (Earth being non-spherical), IIRC something vaguely like half a degree/day difference out of several deg/day, slowly changing plane westward. Thus plane changes take weeks of drifting. Launch being far more about "go fast (in some direction)" than "while being high", rapid plane change (direction change) would have prohibitive "launch-like" energy cost. So a single launch will populate one or few nearby planes. And finally lower orbits orbit faster, quickly overtaking deployed sats in a single plane to reach deployment positions. Kerbal Space Program is thought a fun way to play with such.
They don't break up in to unrelated orbits. They simply spread out along the same orbit by varying the period for a few weeks.
They do raise their orbit to 540-560km from what looks like ~350km launch orbit.
>> https://youtu.be/fEkXTV69yo4?t=22s

Holy S$#! I didn't know about that.

Are there links between this Space Force project and Starlink?

How's this related?
It just shows what an orbiting satellite constellation looks like and why so many are required. That is the similarity
Have you tried to look at the objects not placed by humans?
We need "Space Roombas"™

Starlink was first but what happens when a dozen companies eventually want to put up their own 10,000 low-orbit satellites?

Starlink follows the common solution of having them deorbit and burn up in the atmosphere at EOL. Competitors likely will do the same.

Traffic management is an ongoing debate with the current solution simply being ground based tracking and orbit management.

Until your space roomba hits space debris going the opposite direction and becomes even more space debris
How would that work? A rocket launches into orbit an unmanned satellite capable of autonomously intercepting the orbit of debris in order to collect it and then deorbit itself? Seems extremely expensive for little benefit.

It's my understanding that atmospheric drag and orbital perturbations due to the gravity of other celestial bodies cause satellites to need station keeping maneuvers just to avoid crashing into the Earth. So it seems to me that this debris problem will eventually take care of itself.

Can someone fill me in quickly on what are "instruments"?
the radars collecting the information
This made me look up a link to my old favourite for this kind of thing, CelesTrak.org . Unfortunately, they discontinued their visualizer due to licensing problems.

For posterity, this was the tutorial: https://www.youtube.com/watch?v=wC90GyHMabk

The announcement is here: https://twitter.com/CelesTrak/status/1547264390650527744

For now, the person behind it's got a (informative) error message showing up: https://celestrak.com/cesium/orbit-viz.php

He's asking for donations, might be worth it. It was a good tool.

The ask comes from T.S. Kelso who is well regarded in the orbit tracking/space debris field. He's done a lot of important work making this information public and a lot of public good for collision avoidance. If it's important to you feel free to offer support! It's not clear to me he's asking for money, probably just help and time.
How is this built? Is this built on d3.js? This reminded me of old flash style plugins which we don't see any more.
I don't know which framework they're using, if any, but this is WebGL2. You can write fairly modern OpenGL code and run it in the browser. :)
Imagine if this was to scale and each of the satellites was a giant floating city the size of Tokyo or LA? I wonder how many centuries will pass before that becomes a reality.

It's sort of interesting that there's been a wonky steam punk movie about battling cities roaming the Earth, gobbling each other up, but none about the more plausible future where there are battles between giant orbiting cities who pass their hated rivals once every certain number of years.

Enable Debris and be shocked.
Most of those debris dots however aren't labeled; I wonder if they are actual debris.
It's a simulation of the number of smaller pieces of debris, but not their specific orbits.
Try ground view with debris on.

It looks like Asteroids after you've shot them into 10,000 micro asteroids.

Just needs a UFO going pew-pew...

How do you launch a satellite without risking running into one of these things on the way up? Do you have to calculate the trajectories of all of them individually?
Yes they do know the trajectories so you put yours in a one where it should not hit anything. Most modern satellites also have engines so they can move on their orbit to dodge stuff if needed. Also remember that space is 3 dimensional so you can be at the same exact "spot" on this map but still be few kilometers apart.

Also this visualization is kind of misleading as it makes the satellites look way too big. In reality you could not even see them from even from the closest zoom available.

Yes. But luckily computers are fast and the spaces between each of those dots is (usually) pretty big.
Regarding launching and collisions: You mostly don't have to worry about it. The visualization makes space look crowded, but each satellite is over 150,000 times smaller than what is visualized. Space is very very big and very very empty. LEO is bigger than the surface of the earth and dozens of times thicker than the earth's crust.

It only takes a few radar stations to track all the satellites, and the US Space Force makes their data public.[1][2] Most satellites don't have much in the way of maneuvering capabilities, so you don't need continuous tracking, just updates every few days or so.

1. https://en.wikipedia.org/wiki/United_States_Space_Surveillan...

2. https://www.space-track.org/documentation#api

I guess this is US only? The site is horribly broken upon loading. Only after using developer tools I discovered that all scripts and assets return 403 - CloudFront configured to block your country.

Edit: I'm in Hong Kong.

This is truly fascinating.
Does anyone know what the altitude scaling is on this?
Should be scaled accurately in xyz, just the size of the objects is exaggerated.
Are the speed realtime? It seems they are really fast.
I think if you set speed to 1, it's realtime.
Setting the speed to 1 will make the clock tick at 1 second per second.