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Humans are like satellites in orbit ... inert. It'll only take something like a starlink satellite punching a hole through the ISS for this to register or change anything ... c.f. light pollution
That would be difficult since Starlink orbits more than 100km higher than the ISS.
It's important to note that Starlink satellites will maneuver when they calculate a 1-in-100,000 probability of collision.[0] Most other satellite operators will only maneuver when they predict a 1-in-10,000 chance. The scaling isn't linear either. By setting the threshold 10x lower, SpaceX performs more than 10x as many maneuvers. Essentially they're complaining because SpaceX is too cautious . [0] https://www.space…
But it is a dilemma. Having both so many more satellites than anyone else (SpaceX semi recently crossed the line to having more than half the satellites in orbit) and by having such a lower risk tolerance, I have to wonder if it is a phase shift for LEO.
It feels like orbital tracking models have, for a while, been fairly static. We know where everything is & where it's headed, & only have to make a couple of updates. Operators jobs are relatively simple in this world.
But as the number of satellites keeps increasing, and as they become more likely to manuver, it feels like we shift into a new phase, where we have to have much more dynamic planning. The article says we are up to 69 avoidances a day, 69 times where every other operators now need to see, am I still ok and for how long?
We're probably not there yet, but this idea of space going from mostly static to dynamic would be a huge shift. Also note, SpaceX has lightweight low cost craft with cheap argon thrusters & semi disposable craft; most operators have bigger heavier craft with more limited & expensive maneuvering capabilities: structurally SpaceX is set up to survive a chaotic system, and others will have more expense/difficulty if orbital planning becomes increasingly dynamic.
Earlier quoted context omitted.
As long as other satellites keep being launched into higher but not geosync orbits doesn't that provide a steady supply of junk to navigate around?
> As long as other satellites keep being launched into higher but not geosync orbits doesn't that provide a steady supply of junk to navigate around? Sort of. 1. Modern satellites don't really shed junk - and almost all satellites today have to be launched with a plan to make sure that they deorbit in a timely manner. Doesn't always work out, but most are pretty safe. 2. For space junk, the time to deorbit increases…
Earlier quoted context omitted.
> There’s traffic in space. Is there? I mean obviously there are other satellites, but typically the framing has been that space and LEO is so big that it doesn't matter. That even with all the other satellites you typically don't need any sort of course correction except in very rare circumstances. Isn't the better analogy 'I used to never need to do any swerving at all on my morning commute, but now I need to do it…
There's a space object and debris tracking visualization at http://astria.tacc.utexas.edu/AstriaGraph/ You can filter to "Low Earth Orbit" and play at 100x speed to get an idea of how things are moving around. There's a lot of intersecting paths, a lot of them Starlink satellite trains.
It's important to note that Starlink satellites will maneuver when they calculate a 1-in-100,000 probability of collision.[0] Most other satellite operators will only maneuver when they predict a 1-in-10,000 chance. The scaling isn't linear either. By setting the threshold 10x lower, SpaceX performs more than 10x as many maneuvers. Essentially they're complaining because SpaceX is too cautious . [0] https://www.space…
If you have 4000 satellites a 1-in-10,000 chance doesn't seem that unlikely anymore. The scale of their operation forces them to be more cautious
So SpaceX does a smart, responsible thing here. They make a course adjustment if the probability is above a small threshold (probably 10^-5). From my understanding this is all automated. It's not a "swerve" or an emergency. Their satellite simply needs to adjust its normal orbit-keeping thrust a small amount at some point in the next 12-24 hours. It's table-stakes for constellation management at this point. Planet does the same tracking with their 100-200 Dove satellites.
Additionally, SpaceX and other operators like Planet have higher fidelity tracking data than the USSF's radar data (available at https://www.space-track.org with a free account or through https://celestrak.org). They publish their tracking data for other operators (https://ephemerides.planet-labs.com). Having lower error-bounds reduces the number of potential collisions that need to be avoided and tracked.
Inflammatory language like this is frustrating because it feeds an emotional "have you heard about Kessler Syndrome!?!" gut response. Many people and VCs have been duped into spending time on exotic stuff like harpoon capture and trash collecting satellites. But the answer, to anyone who actually works on this problem and does any research, is already there. What SpaceX and Planet are doing is responsible. Debris mitigation agreements and deorbit timeline restrictions from the FCC/other bodies are enough. If someone truly does launch 10-100k satellites, there are great solutions available with defined orbital bands.
If SpaceX had done 0 of these maneuvers it's unlikely anything bad would have happened. But they're doing the right thing here. And Starlink satellites are very low and don't stick around as junk when they're not being used. Basically, the tone here should be "wow SpaceX does a great job with automating collision avoidance", not "satellites constantly swerving in space".
It's important to note that Starlink satellites will maneuver when they calculate a 1-in-100,000 probability of collision.[0] Most other satellite operators will only maneuver when they predict a 1-in-10,000 chance. The scaling isn't linear either. By setting the threshold 10x lower, SpaceX performs more than 10x as many maneuvers. Essentially they're complaining because SpaceX is too cautious . [0] https://www.space…
If you have 4000 satellites a 1-in-10,000 chance doesn't seem that unlikely anymore. The scale of their operation forces them to be more cautious
I recently took my first dive into Celestrak which provides coordinates (TLE's) for all sorts of satellites. Fascinating project I want to learn more about how changes in trajectory are executed by different operators and are communicated more broadly. Here's some of their Starlink data: https://celestrak.org/NORAD/elements/table.php?GROUP=starlin... More on the TLE format from wikipedia: https://en.wikipedia.org/wik…
Earlier quoted context omitted.
If you have 4000 satellites a 1-in-10,000 chance doesn't seem that unlikely anymore. The scale of their operation forces them to be more cautious
When you've got that many, you've got to expect to lose more than a few. Right?
There's enough atmosphere in those low orbits that chain reactions aren't a huge concern for the rest of human spaceflight, but they are a concern for keeping the Starlink constellation alive.