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.
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.)
Thank you!
Does this mean the US probably has satellites that can easily pick up cell signals anywhere in the world from space?
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.)
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.
Holy S$#! I didn't know about that.
Are there links between this Space Force project and Starlink?
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...
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"?
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).
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
Each dot here represents things at most meters large. Most are centimetres large especially if you look at debris. Yet each dot is the size of a large urban area on Earth. Do the same thing with planes or boats and the Earth will be close to painted a solid colour.
Obviously, to size, you would see nothing from this distance which would be a lot less impressive, a lot less useful but a lot less scary.
I was expecting this, since it's probably the most common criticism of this type of visualization.
Problem is, that analysis only looks at half the dataviz fidelity coin. It recognizes the (unavoidable) loss of fidelity in size, but it ignores the (also unavoidable) loss of fidelity in time.
In the real world these objects do not remain orbiting Earth for a few minutes (ie the interval you're likely to look at this visualization). Instead, objects above ~800 km remain in Earth orbit for hundreds to thousands of years.[1]
Mathematically this second inaccuracy tends to cancel out the first inaccuracy, therefore (presumably) making this "a lot more scary/impressive."
Strangely I always see the criticism about size, but I never see the countervailing criticism about time. I suppose it's just like you said: the size factor is "obvious", but the time factor much less so.
Eta: For some great visualizations of the space debris problem, I can heartily recommend this (slightly older) ESA video.[2] It's basically a full-length documentary crammed into 15 minutes.
[1] https://commons.wikimedia.org/wiki/File:Orbital_Debris_Lifet...
I.e. the likelihood of hitting an object using a LEO view that is facing parallel to the earth's surface below the viewer
The idea is that in every direction is a color map indicating probability of hitting an object if going straight in that direction to infinity, or till reaching earth's surface (for downward angles), assuming all the objects are frozen in time
Not sure how to represent earth's surface though without fudging the color map colors, so maybe scratch that or use outlines to represent continents instead of surface color
Its an idea maybe?
No more scary than the number of airplanes in the air at any given time, which is a similar order of magnitude. flightradar24 tracks around 200k flights per day — there's probably ~10k–20k aircraft in the air at any time.
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!
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.
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.
Side note: does anyone know of a good tool / app for looking at things like that on iOS ?
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?
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.
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.
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...
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.
[1]: https://github.com/mrdoob/three.js/
It looks like Asteroids after you've shot them into 10,000 micro asteroids.
Just needs a UFO going pew-pew...
Starlink was first but what happens when a dozen companies eventually want to put up their own 10,000 low-orbit satellites?
Traffic management is an ongoing debate with the current solution simply being ground based tracking and orbit management.
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.
For more detail than you ever wanted, check here: https://mikepuchol.com/modeling-starlink-capacity-843b2387f5...
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.
We worry about orbital debris because of the consequence of loss. There's a lot of room up there (not discounting everyone's concern).
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.
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)
Do you know if there's been any news on KSP2? At this point I'm not sure it will ever happen.
Is it unity or Godot or something?
Edit: I'm in Hong Kong.
Even 10 years ago, that thought would have been ludicrous.
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.
