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SpaceX Refused to Move Satellite at Risk of Collision with a European Satellite

183 points by johnny313 7y ago

throwaway2048 7y ago
From the twitter thread: It is very rare to perform collision avoidance manoeuvres with active satellites. The vast majority of ESA avoidance manoeuvres are the result of dead satellites or fragments from previous collisions. [ ... ] As the number of satellites in orbit increases, due to 'mega constellations' such as #Starlink comprising hundreds or even thousands of satellites, today's 'manual' collision avoidance process will become impossible...
- floatingatoll 7y ago
  This is unreadable on mobile due to the use of code formatting. https://i.imgur.com/562ORgL.png https://i.imgur.com/562ORgL.png EDIT: Said comment is now one full screen tall due to manual insertion of linewraps, and is very wasteful of space on desktop and landscape layouts: https://i.imgur.com/H15eCXo.png https://i.imgur.com/H15eCXo.png
  - pxtail 7y ago
    It so weird that there is no incentive to fix many usability shortcomings like this one and too tiny UI elements on mobile etc. - all of that despite multiple complaints over years..
    - saagarjha 7y ago
      It’s meant for code, where the browser isn’t necessary very good at wrapping lines.
    - floatingatoll 7y ago
      Mobile works fine for me and the UI elements as shown honor my text size setting accurately. Using code formatting for non-code results in broken formatting for non-code. This should come as no surprise to anyone. Indents aren’t worth a semantic violation. Use “> ” prefixes like classic email, and optionally italic asterisks if that’s desirable.
  - irq 7y ago
    There was a post on HN yesterday thanking the operators for never updating the site. While I mostly agree with that sentiment, this code formatting BS is an outlier and very much needs to be addressed. Either take the feature away altogether, or just make it work well on mobile. But this middle ground where HN visitors inadvertently ruin their contributions for mobile users is bad.
- jonsen 7y ago
  It is very rare to perform collision avoidance manoeuvres with active satellites. The vast majority of ESA avoidance manoeuvres are the result of dead satellites or fragments from previous collisions. [ ... ] As the number of satellites in orbit increases, due to 'mega constellations' such as #Starlink comprising hundreds or even thousands of satellites, today's 'manual' collision avoidance process will become impossible...
weinzierl 7y ago
For anyone not familiar with aerospace terminology: LEO is not the name of the satellite but just means that it is a low flying satellite. It stands for Low Earth Orbit.
jazzyjackson 7y ago
How is it the case that StarLink didn't realize they were launching into orbits that would intersect with others? I find it foreboding that the number of intersections with space debris and live constellations is to the point where ESA is moving towards non-deterministic algorithms to hopefully avoid the worst. How will Musk ever leave this planet if we make a shell of debris around ourselves? See also: the anime "planetes"
- inamberclad 7y ago
  They don't plan like that at all. Since all these orbital parameters change over time due to atmospheric drag, solar pressure, gravity irregularities, etc, organizations like NORAD constantly monitor and determine the orbital parameters of every object they can find circling the Earth. So, they watch for when the likelihood that one satellite will come within some small distance (say, 5km) of another is high. For example, if the odds that they come that close are say, 75% in the next 5 orbits, the operators are notified and alter their courses slightly to maintain separation. Even manned spacecraft such as the ISS will perform separation maneuvers to keep themselves clear of objects that may come too close.
  - perl4ever 7y ago
    I think the issue is that people have some vague affinity for the way space travel was depicted in old science fiction, where you could blast off and manually control everything with possibly the assistance of a slide rule. And it's slightly discomfiting to realize that just traffic control is so complex that it needs modern computers to track and react. Space is supposed to be vast and empty! And it is, but not in LEO.
- floatingatoll 7y ago
  Clearly we need to invent ESA a Space-debris Hunting semi-Automomous Reconnaissance Craft, with a solar-powered infrared heating beam to shatter the frozen space material into ever-smaller bits. Or, as I like to call this class of spacecraft - SHARCs with frackin’ laser beams
- ClumsyPilot 7y ago
floatingatoll 7y ago
> In 2018, ESA performed 28 #collisionavoidance manoeuvres across its fleet.
- edoceo 7y ago
  One every two weeks (about) don't seem "rare" to me.
  - throwaway2048 7y ago
    Its rare to have to avoid an active satellite, rather than random orbiting garbage.
- pergadad 7y ago
  How many maneuvers can such a satellite do with it's limited fuel?
  - greglindahl 7y ago
    The Aeolus satellite needs to be reboosted on occasion due to atmospheric drag. So, potentially, it was free.
    - deleted 7y ago
      [deleted]
konschubert 7y ago
I wonder if AI is really the right tool to automate the process. Couldn’t it be done more robustly with a simple algorithm that takes todays collision probability models as input?
- carlosdp 7y ago
  I imagine we might be missing some details, but I agree. Seems like business logic would be sufficient if the collision prediction can be piped in.
- deleted 7y ago
  [deleted]
- pergadad 7y ago
  How much thrust? How high should it go? And on what information? Data sources will become more complex, risks need to be weighed. I'm not sure 'AI' is the right answer as most (all?) of AI is probably today just ML or more often simple BS - but certainly what ESA & co need won't be a simple one-variable algorithm. I'm actually wondering if there's not a need to communicate more between all the bodies having satellites in space - just like autonomous cars, if both make an evasive maneuver they might cancel each other out. So there needs to be some kind of communication to avoid this.
  - perl4ever 7y ago
    "just like autonomous cars, if both make an evasive maneuver they might cancel each other out" I think that's a phenomenon much older than autonomous car theory. https://www.urbandictionary.com/define.php?term=Hallway%20dance https://www.urbandictionary.com/define.php?term=Hallway%20da...
- orbital-decay 7y ago
  - most popular orbits are also most crowded and dangerous ones, there's only so much you can do to reduce the probability of collision - there are also uncontrolled debris, non-tracked objects, military satellites with unpublished orbits etc - just like with automating road vehicle traffic, it would require very high degree of centralization, which is never going to happen due to various reasons - the propellant is limited so you also want to reduce the amount of avoidance maneuvers to a minimum So no, statistical models (which you probably mean by AI) won't improve the situation much. What matters is: - increasing the orbit determination accuracy and coverage with better instruments and commercial tracking networks; NORAD TLEs alone are not precise enough for reliable collision prediction - better space weather prediction - improving the coordination between the operators - deployable decelerators for dead satellites in lower orbits, also possibly debris removal if the problem becomes really serious i.e. stuff most operators already do, except for the debris removal
saagarjha 7y ago
Of course, inside the article it’s explained that SpaceX didn’t “refuse” to move the satellite, they were politely asked to do so and declined for reasons the author is unaware of. Possibly because they couldn’t move the satellite or had a higher collision tolerance.
- vvanders 7y ago
  The thing is that satellites are planned with a lifespan which can include a fixed amount of fuel for adjustments like this. It's not too hard to attach a dollar amount here. I'm as big a fan of SpaceX as you'll find but considering they were the one entering an orbit they didn't previously occupy it seems like a pretty lame move on SpaceX's part.
  - londons_explore 7y ago
    I bet their actions would have been different if they'd known this article would be published. It puts them in a bad light, and that could impact their ability to get necessary licenses to operate.
  - grecy 7y ago
    I suppose that's going to be a question in the coming years - does someone get the right of way to a given orbit just because they were there first? Sounds like a fantastic barrier to entry for newcomers who don't have billions lining their pockets.
    - phkahler 7y ago
      That is true of all finite resources, from orbits to spectrum to real estate.
      - tomjakubowski 7y ago
        Maybe the United Nations (or future world government) could levy an Earth-orbital value tax to ensure orbits are used efficiently.
syx 7y ago
Everytime I see these kind of events I think about Kurzgesagt video [1] about how the domino effect of satellite collisions would release such a high amount space debris that would trap us all on earth forever. [1] https://www.youtube.com/watch?v=yS1ibDImAYU https://www.youtube.com/watch?v=yS1ibDImAYU
- dvtrn 7y ago
  Has this ever been explored as a Fermi solution? I realize it’s probably on the wild side of speculation but...
  - SamReidHughes 7y ago
    It just means orbits at one level are out of the question. You can still punch through to a higher orbit.
- felipemnoa 7y ago
  Related anime: https://myanimelist.net/anime/329/Planetes https://myanimelist.net/anime/329/Planetes
- oh_sigh 7y ago
  Starlink satellites are only approximately 350 miles up, which means any debris gets brought down by atmospheric drag very quickly. A million satellites in that orbit could not cause kessler syndrome.
  - ClumsyPilot 7y ago
    That's not quite accurate. Firstly,the debris will destroy everything in LEO, maybe including ISS, then debit in a few months. Secondly, some of the debris will probably end up in higher orbit and stay there for a long time, just like was the case with India and China ASAT tests. Then they can pose a risk for centuries
    - Rebelgecko 7y ago
Jyaif 7y ago
It's like when there's a crappy car refusing to give the right a way to a luxury car. The crappy car owner has little to lose compared to the luxury car owner. Constellation owners (SpaceX here) knows that owners of big satellite will dodge them. Big satellite will have to carry more fuel, which incidentally is good news for the business of satellite launchers (SpaceX again).
cameronbrown 7y ago
Why would they refuse to move the satellite? It's not like only the European satellite would be affected by a collision, both are in danger, so either they couldn't or they didn't think it was likely.
- Tuna-Fish 7y ago
  The likely answer is that the satellite in question was out of control and they couldn't move it. I don't know which Starlink sat this was, but the the other satellite that did dodge seems to be flying at ~300km. This is much lower than what the functional Starlink constellation is. Some of the initial launch failed to unfold their solar panels, and the batteries would have ran down by now, so they are rapidly decaying space trash. Others are being deorbited under power but SpaceX would have no reason not to do dodge with those.
  - tssva 7y ago
    The article clearly states that the SpaceX satellite was at this position because they were deorbiting it under power.
  - semi-extrinsic 7y ago
    Why are they deorbiting? Didn't they just launch these?
    - duskwuff 7y ago
      To test their ability to perform a controlled deorbit.
      - fwip 7y ago
        Sounds like the test didn't work, if they can't avoid hitting other satellites.
    - foobiekr 7y ago
      They are test satellites with no lateral switching capability.
rocqua 7y ago
I presume there are liability rules if your satellite hits another one. What about if your satellite makes another one waste fuel on a diversion?
- avocado4 7y ago
  Would ESA satellite hit Space X or the other way around? How do they determine it?
  - jsiepkes 7y ago
    The ESA satellite had been on that orbit 9 months before the Spacelink satellite.
- peteretep 7y ago
  Where would have jurisdiction?
  - mises 7y ago
    I could see them going after a european company, or America going after an American company. I'm guessing the europeans are going to insist they want it done in their courts, and SpaceX is just gonna shrug and say, "Nope, not showing up." europeans can't really make an American company do much.
    - peteretep 7y ago
      > europeans can't really make an American company do much There's very few large American companies for whom the EU is neither a huge market, nor a major location.
- mlindner 7y ago
  By international space law full liability is held by the country of launch/license. The US Government would owe the ESA a full paycheck if it was to be damaged. So this is already well covered in international law.
londons_explore 7y ago
The US military tracking isn't very accurate. Errors of hundreds of meters are common. I bet spacex themselves know the location of their satellites to within a few meters. With more accurate data, you can come up with a far more accurate collision risk estimate.
- SiempreViernes 7y ago
  Ok, so by which physical method do they have better telemetry?
  - DuskStar 7y ago
    Active transponders on the satellite itself. GPS fixes. Other observations from the satellite. Controlling the target makes some problems a lot easier.
    - SiempreViernes 7y ago
      GPS appears to not give great online performance in LEO[1], and transponders is just slightly easier radar, not a fundamental difference. Do they have really good star trackers on their sats? [1]: https://space.stackexchange.com/questions/563/in-leo-what-is-the-precision-of-gnss-based-position-compared-to-traditional-met https://space.stackexchange.com/questions/563/in-leo-what-is...
      - dtkav 7y ago
        They don't need great online performance, they need offline performance for orbit determination. Once they have a good orbit fit, they will propagate it to predict the probability of collision a few days in advance.
  - dtkav 7y ago
    gps (NORAD is using radar)
  - debatem1 7y ago
areoform 7y ago
Being a lover of Space and SpaceX, this incident highlights why a goldilocks paradigm for regulation needs to exist for space. Not too much that it stifles innovation. Not too little that someone ends up Kesslerizing Near-Earth space. Current regulations are largely successful at promoting commercial space flight, but there is a big transparency gap between civilian space flight agencies and private entities. Transparency should be one of the cornerstones of space regulations, but it isn’t. This incident raises multiple policy questions. Why can’t SpaceX move their satellite? Is it a no because an ion drive takes days to burn or is it a no because they don’t wanna? Either way, it exposes a flaw in SpaceX’s design and raises concerns about StarLink. When there are hundreds of StarLink satellites in the air, will SpaceX say no again if there’s a chance for collision? Will SpaceX be a responsible steward of Near-Earth space? If ion drives are insufficient to address this problem, should they be required to take a small amount of monopropellant as a precaution? Transparency is essential for answering these questions and asking new ones. The one I’m most concerned about is the question, what are the pollution risks of LEO constellations? Ideally, before StarLink and other networks are up and running, I feel there should be a study of the pollution risk StarLink poses be it light pollution or debris. We shouldn’t repeat the failings of the 20th century in space.
- deleted 7y ago
  [deleted]
- avocado4 7y ago
  > Either way, it exposes a flaw in SpaceX’s design What is this statement based on? You are saying yourself that there's no information available to the public about this due to lack of transparency, yet in the next sentence you are making a bold statement about design flaws. To me it sounds like there should be clear regulation about right of way in space. I haven't seen any information pertaining to SpaceX design so far.
  - dahdum 7y ago
    > To me it sounds like there should be clear regulation about right of way in space Common courtesy worldwide would be for the person causing the risk to move aside first. Worse still it was a private company working on a for-profit product forcing a public weather satellite to divert. There's no need for regulation until bad actors show up.
mabbo 7y ago
The ESA is sure making a huge deal out of this. I wonder if politics is involved. https://twitter.com/IridiumBoss/status/1168582141128650753 https://twitter.com/IridiumBoss/status/1168582141128650753 > Hmmm. We move our satellites on average once a week and don't put out a press release to say who we maneuvered around... -Matt Desch, CEO of Iridium
- avocado4 7y ago
  > In 2018, ESA performed 28 #collisionavoidance manoeuvres across its fleet.
  - FireBeyond 7y ago
    ... typically of dead satellites or debris that is unable to move itself. ESA had a weather satellite in orbit, SpaceX actively moved an active satellite _into_ the same orbit as ESA's satellite (to practice maneuvers) and then said "no, we won't move it back out the way".
    - manicdee 7y ago
      No. All deorbiting objects (“satellites” or debris, whatever you want to call them) are going to pass through the orbit of the ESA satellite which is intentionally in a very low orbit. It is the ESA that actively moved into that orbit by design, intention and active navigation. SpaceX intended their satellite to lift to a higher orbit but it couldn’t make it, so it is being deorbited by atmospheric drag. All orbits at the same altitude will cross at least twice. This is not a deliberate act of interception but just part of the way orbits work.
      - FireBeyond 7y ago
        That article started that the Spacelink satellite -had- been at a much higher orbit (the "regular" for their satellites, but had been brought down "to test de-orbiting maneuvers". Do you have a source to the contrary? Also, the ESA satellite has been in that orbit for 8+ years. It wasn't "moved" into the Spacelink orbit by any means. I get that en route to or from orbit, entities will pass through other orbits.
mLuby 7y ago
>ESA noted that it performed 28 collision avoidance maneuvers in 2018, but it was mostly to avoid dead satellites or bits of space debris. Maneuvers to avoid active satellites were “very rare”, they said, but the arrival of mega constellations like Starlink raises concerns that many more such maneuvers will be needed in future. >“What I want is an organized way of doing space traffic. It must be clear when you have such a situation who has to react. And of course automating the system. It cannot be when we have 10,000 satellites in space that there are operators writing the email what to do. This is not how I imagine modern spaceflight.” SpaceX simply saying it would "not act" is negligent, and I really hope there was more to it that the author just wasn't privy to. If they had better sensors and knew there'd be no collision, say so. If they couldn't maneuver, say so. Otherwise it's just a game of space chicken, risking not only those two sats but all of LEO.
- pergadad 7y ago
  One is a throwaway satellite of a huge constellation - the other a unique billion euro research satellite. Easy to see who will give in first to protect their assets, but plainly it is equally easy to see who should move first.
  - oh_sigh 7y ago
    What happens if the two groups disagree on the odds of impact? Because one has either more precise or just different telemetry than the other?
    - safsafasf 7y ago
      There's not much to disagree on the odds. Trajectories are known, uncertainties too and therefore probabilities of collisions can be calculated. Any disagreement here is easy to reconcile, whose assumptions and methods are more accurate? The disagreement is on the importance of the odds. SpaceX might be OK with a 1:10000 (or whatever) chance of collision, the Europeans want it lower. The Europeans could in the future force the issue. Move, or we'll fine you and forbid you from launching off of European sites and ban EU companies from using SpaceX.
everyone 7y ago
https://en.wikipedia.org/wiki/Kessler_syndrome https://en.wikipedia.org/wiki/Kessler_syndrome Yay!!
- guerrilla 7y ago
  Animated version: https://www.youtube.com/watch?v=yS1ibDImAYU https://www.youtube.com/watch?v=yS1ibDImAYU
Steel_Phoenix 7y ago
I was under the impression that most of the constellation would be at such an unusually low orbit that there wouldn't be much to collide with. How crowded are the planned orbit shells?
DreamSpinner 7y ago
What's interesting is that there's already a similar internationally agreed framework for how to approach this - shipping - https://en.wikipedia.org/wiki/International_Regulations_for_Preventing_Collisions_at_Sea https://en.wikipedia.org/wiki/International_Regulations_for_... - These would probably be a good place to start considering a framework for satellite orbit adjustments. However, despite this framework, it still happens - and I can see the issue of risk evaluation being a big one - what if one entity thinks a 1/1000 risk is acceptable for their cheap satellite vs the other satellite wanting 1/1000000?
- pmyteh 7y ago
  You're liable for damage to the other party if you're at fault for a maritime collision, so there's at least some countervailing economic pressure against taking the risk. Your insurers will not be happy with you if you negligently sink someone else's oil tanker.
- frankharv 7y ago
  I agree with this. Rules of the seas are not laws but more like a code for mariners to follow. Too bad we see such ignorance in space. Think of the ESA bird as a "boat in anchor". Lit up with the proper anchorage lights. Now some jackass with a jetski is blasting right twords you.
dmix 7y ago
> ESA is preparing to automate this process using #AI Sounds like something SpaceX and other constellation satellite companies should do as part of these widescale deployment. Or at least lower the threshold of moving out of the way so they don't get tons of push back from existing space power players who’ve got more influence than they do.
dzhiurgis 7y ago
Is there any right of way rules similar to how marine traffic works?
ricardobeat 7y ago
Judging by the comments here, this piece has succeeded in planting the idea that StarLink is dangerous using incredibly little detail.
- asdff 7y ago
  More like "Musk company does something arrogant again"
mises 7y ago
This is gonna get ugly pretty soon. I'm pretty convinced it's less an issue of moving (which esa itself stated it does once every week to two weeks) and more of politics. A couple possibilities: * europe mad at America b/c trade * europe mad at American companies beating european ones to space and getting more of the limited orbit spots first * europe mad she wasn't really asked before SpaceX put up satellites * europe has a principal objection to the idea of private companies playing on the same level as the bureaucrats or an issue with corps occupying space at all Most likely, it's a combination of all of the above. Regardless, people will start getting awfully catty about this, and it's possible knocking some one else's satellite out of the sky could be a serious issue.
zaroth 7y ago
NORAD 44278 is a Starlink satellite presently being de-orbited by SpaceX in a controlled fashion to simulate end-of-life disposal. [1] The current altitude (~330km) [2] puts it well below the operation envelope and it’s currently the lowest sat of the Starlink constellation at this point. It appears SpaceX does continue to have some level of control of the craft. [3] Some speculation I’ve read is that the much higher impulse of the ESA thrusters would make the ESA craft a better candidate to execute the maneuver. These adjustments are not rare - they happen approximately every other week for this particular craft, and as Iridium says, they do this weekly. [4] A video of the conjecture [5] shows an approach of “less than 10km”. The ESA craft apparently passed much closer to several other craft over the last week, so there may be more to it in this case, or there may be a bone to pick with Starlink. Lastly, ESA has a particular interest in raising this issue now as much as possible, as these “mega-constellations” launched by US companies are coming closer to reality and the current processes (picking up the phone) don’t scale well to tens of thousands of satellites. [1] - https://twitter.com/thesheetztweetz/status/1144689334777524226?s=21 https://twitter.com/thesheetztweetz/status/11446893347775242... [2] - https://www.n2yo.com/satellite/?s=44278 https://www.n2yo.com/satellite/?s=44278 [3] - https://twitter.com/planet4589/status/1168637324592328705?s=21 https://twitter.com/planet4589/status/1168637324592328705?s=... [4] - https://twitter.com/iridiumboss/status/1168582141128650753?s=21 https://twitter.com/iridiumboss/status/1168582141128650753?s... [5] - https://twitter.com/m_r_thomp/status/1168583891726344193?s=21 https://twitter.com/m_r_thomp/status/1168583891726344193?s=2...
- manicdee 7y ago
  The “more to it” is that ESA is gearing up to request funding for their AI project, billed as an automated tracking and avoidance manoeuvre planning system capable of handling the vast numbers of objects and debris expected to be in orbit in the near future. This was not about “SpaceX refused to move” but “we need money to build this automated system so we don’t have to do it all by hand,” and an additional level which is, how should the various satellite operators make their orbital parameters available to interested parties? The situation is that ESA didn’t even know what kind of object the track represented, and they had to contact SpaceX to ask about it in the first place. Their job would have been easier (whether manual or automated) if SpaceX made the orbital parameters available for automated queries. The last thing this is about is SpaceX being “arrogant” or “refusing to move a satellite.”
newnewpdro 7y ago
I guess when you have your own launch capabilities you can treat your internet satellites as easily replaced. Adding more junk up there only serves to create more launches as the inevitable collisions occur. It arguably makes good business sense for SpaceX to add as much as possible and be quite fast and loose with their management of it, at least as long as it's the wild west up there.
WalterBright 7y ago
The long term solution would be to establish some form of property rights over particular orbits. Then, to use a particular orbit, one must pay the market rate for it.
- greglindahl 7y ago
  Deorbiting satellites make that a hilarious proposal.
  - WalterBright 7y ago
    Certainly property rights to orbits will have special characteristics. We've already accumulated much experience with property rights for things that are different from physical property - I'm sure spending more than 30 seconds thinking about it can come up with solutions.
mlindner 7y ago
This is a false article. There is no evidence SpaceX refused to move and ESA calling out the fact that they moved for a SpaceX satellite is ESA playing politics. LEO is full of space debris and satellite owners move satellites for space junk all the time. This is called political grandstanding.
mLuby 7y ago
"SpaceX, in a new statement, says they were aware of the potential Aeolus/Starlink collision, but at first the probability was low. When the probability increased, “a bug in our on-call paging system prevented the Starlink operator from seeing the follow on correspondence.”" https://twitter.com/jeff_foust/status/1168919094265044996 https://twitter.com/jeff_foust/status/1168919094265044996

183 points by johnny313 7y ago

throwaway2048 7y ago

From the twitter thread: It is very rare to perform collision avoidance manoeuvres with active satellites. The vast majority of ESA avoidance manoeuvres are the result of dead satellites or fragments from previous collisions. [ ... ] As the number of satellites in orbit increases, due to 'mega constellations' such as #Starlink comprising hundreds or even thousands of satellites, today's 'manual' collision avoidance process will become impossible...

floatingatoll 7y ago
This is unreadable on mobile due to the use of code formatting. https://i.imgur.com/562ORgL.png https://i.imgur.com/562ORgL.png EDIT: Said comment is now one full screen tall due to manual insertion of linewraps, and is very wasteful of space on desktop and landscape layouts: https://i.imgur.com/H15eCXo.png https://i.imgur.com/H15eCXo.png
- pxtail 7y ago
  It so weird that there is no incentive to fix many usability shortcomings like this one and too tiny UI elements on mobile etc. - all of that despite multiple complaints over years..
  - saagarjha 7y ago
    It’s meant for code, where the browser isn’t necessary very good at wrapping lines.
  - floatingatoll 7y ago
    Mobile works fine for me and the UI elements as shown honor my text size setting accurately. Using code formatting for non-code results in broken formatting for non-code. This should come as no surprise to anyone. Indents aren’t worth a semantic violation. Use “> ” prefixes like classic email, and optionally italic asterisks if that’s desirable.
- irq 7y ago
  There was a post on HN yesterday thanking the operators for never updating the site. While I mostly agree with that sentiment, this code formatting BS is an outlier and very much needs to be addressed. Either take the feature away altogether, or just make it work well on mobile. But this middle ground where HN visitors inadvertently ruin their contributions for mobile users is bad.
jonsen 7y ago
It is very rare to perform collision avoidance manoeuvres with active satellites. The vast majority of ESA avoidance manoeuvres are the result of dead satellites or fragments from previous collisions. [ ... ] As the number of satellites in orbit increases, due to 'mega constellations' such as #Starlink comprising hundreds or even thousands of satellites, today's 'manual' collision avoidance process will become impossible...

weinzierl 7y ago

For anyone not familiar with aerospace terminology: LEO is not the name of the satellite but just means that it is a low flying satellite. It stands for Low Earth Orbit.

jazzyjackson 7y ago

How is it the case that StarLink didn't realize they were launching into orbits that would intersect with others? I find it foreboding that the number of intersections with space debris and live constellations is to the point where ESA is moving towards non-deterministic algorithms to hopefully avoid the worst. How will Musk ever leave this planet if we make a shell of debris around ourselves? See also: the anime "planetes"

inamberclad 7y ago
They don't plan like that at all. Since all these orbital parameters change over time due to atmospheric drag, solar pressure, gravity irregularities, etc, organizations like NORAD constantly monitor and determine the orbital parameters of every object they can find circling the Earth. So, they watch for when the likelihood that one satellite will come within some small distance (say, 5km) of another is high. For example, if the odds that they come that close are say, 75% in the next 5 orbits, the operators are notified and alter their courses slightly to maintain separation. Even manned spacecraft such as the ISS will perform separation maneuvers to keep themselves clear of objects that may come too close.
- perl4ever 7y ago
  I think the issue is that people have some vague affinity for the way space travel was depicted in old science fiction, where you could blast off and manually control everything with possibly the assistance of a slide rule. And it's slightly discomfiting to realize that just traffic control is so complex that it needs modern computers to track and react. Space is supposed to be vast and empty! And it is, but not in LEO.
floatingatoll 7y ago
Clearly we need to invent ESA a Space-debris Hunting semi-Automomous Reconnaissance Craft, with a solar-powered infrared heating beam to shatter the frozen space material into ever-smaller bits. Or, as I like to call this class of spacecraft - SHARCs with frackin’ laser beams
ClumsyPilot 7y ago

floatingatoll 7y ago

> In 2018, ESA performed 28 #collisionavoidance manoeuvres across its fleet.

edoceo 7y ago
One every two weeks (about) don't seem "rare" to me.
- throwaway2048 7y ago
  Its rare to have to avoid an active satellite, rather than random orbiting garbage.
pergadad 7y ago
How many maneuvers can such a satellite do with it's limited fuel?
- greglindahl 7y ago
  The Aeolus satellite needs to be reboosted on occasion due to atmospheric drag. So, potentially, it was free.
  - deleted 7y ago
    [deleted]

konschubert 7y ago

I wonder if AI is really the right tool to automate the process. Couldn’t it be done more robustly with a simple algorithm that takes todays collision probability models as input?

carlosdp 7y ago
I imagine we might be missing some details, but I agree. Seems like business logic would be sufficient if the collision prediction can be piped in.
deleted 7y ago
[deleted]
pergadad 7y ago
How much thrust? How high should it go? And on what information? Data sources will become more complex, risks need to be weighed. I'm not sure 'AI' is the right answer as most (all?) of AI is probably today just ML or more often simple BS - but certainly what ESA & co need won't be a simple one-variable algorithm. I'm actually wondering if there's not a need to communicate more between all the bodies having satellites in space - just like autonomous cars, if both make an evasive maneuver they might cancel each other out. So there needs to be some kind of communication to avoid this.
- perl4ever 7y ago
  "just like autonomous cars, if both make an evasive maneuver they might cancel each other out" I think that's a phenomenon much older than autonomous car theory. https://www.urbandictionary.com/define.php?term=Hallway%20dance https://www.urbandictionary.com/define.php?term=Hallway%20da...
orbital-decay 7y ago
- most popular orbits are also most crowded and dangerous ones, there's only so much you can do to reduce the probability of collision - there are also uncontrolled debris, non-tracked objects, military satellites with unpublished orbits etc - just like with automating road vehicle traffic, it would require very high degree of centralization, which is never going to happen due to various reasons - the propellant is limited so you also want to reduce the amount of avoidance maneuvers to a minimum So no, statistical models (which you probably mean by AI) won't improve the situation much. What matters is: - increasing the orbit determination accuracy and coverage with better instruments and commercial tracking networks; NORAD TLEs alone are not precise enough for reliable collision prediction - better space weather prediction - improving the coordination between the operators - deployable decelerators for dead satellites in lower orbits, also possibly debris removal if the problem becomes really serious i.e. stuff most operators already do, except for the debris removal

saagarjha 7y ago

Of course, inside the article it’s explained that SpaceX didn’t “refuse” to move the satellite, they were politely asked to do so and declined for reasons the author is unaware of. Possibly because they couldn’t move the satellite or had a higher collision tolerance.

vvanders 7y ago
The thing is that satellites are planned with a lifespan which can include a fixed amount of fuel for adjustments like this. It's not too hard to attach a dollar amount here. I'm as big a fan of SpaceX as you'll find but considering they were the one entering an orbit they didn't previously occupy it seems like a pretty lame move on SpaceX's part.
- londons_explore 7y ago
  I bet their actions would have been different if they'd known this article would be published. It puts them in a bad light, and that could impact their ability to get necessary licenses to operate.
- grecy 7y ago
  I suppose that's going to be a question in the coming years - does someone get the right of way to a given orbit just because they were there first? Sounds like a fantastic barrier to entry for newcomers who don't have billions lining their pockets.
  - phkahler 7y ago
    That is true of all finite resources, from orbits to spectrum to real estate.
    - tomjakubowski 7y ago
      Maybe the United Nations (or future world government) could levy an Earth-orbital value tax to ensure orbits are used efficiently.

syx 7y ago

Everytime I see these kind of events I think about Kurzgesagt video [1] about how the domino effect of satellite collisions would release such a high amount space debris that would trap us all on earth forever. [1] https://www.youtube.com/watch?v=yS1ibDImAYU https://www.youtube.com/watch?v=yS1ibDImAYU

dvtrn 7y ago
Has this ever been explored as a Fermi solution? I realize it’s probably on the wild side of speculation but...
- SamReidHughes 7y ago
  It just means orbits at one level are out of the question. You can still punch through to a higher orbit.
felipemnoa 7y ago
Related anime: https://myanimelist.net/anime/329/Planetes https://myanimelist.net/anime/329/Planetes
oh_sigh 7y ago
Starlink satellites are only approximately 350 miles up, which means any debris gets brought down by atmospheric drag very quickly. A million satellites in that orbit could not cause kessler syndrome.
- ClumsyPilot 7y ago
  That's not quite accurate. Firstly,the debris will destroy everything in LEO, maybe including ISS, then debit in a few months. Secondly, some of the debris will probably end up in higher orbit and stay there for a long time, just like was the case with India and China ASAT tests. Then they can pose a risk for centuries
  - Rebelgecko 7y ago

Jyaif 7y ago

It's like when there's a crappy car refusing to give the right a way to a luxury car. The crappy car owner has little to lose compared to the luxury car owner. Constellation owners (SpaceX here) knows that owners of big satellite will dodge them. Big satellite will have to carry more fuel, which incidentally is good news for the business of satellite launchers (SpaceX again).

cameronbrown 7y ago

Why would they refuse to move the satellite? It's not like only the European satellite would be affected by a collision, both are in danger, so either they couldn't or they didn't think it was likely.

Tuna-Fish 7y ago
The likely answer is that the satellite in question was out of control and they couldn't move it. I don't know which Starlink sat this was, but the the other satellite that did dodge seems to be flying at ~300km. This is much lower than what the functional Starlink constellation is. Some of the initial launch failed to unfold their solar panels, and the batteries would have ran down by now, so they are rapidly decaying space trash. Others are being deorbited under power but SpaceX would have no reason not to do dodge with those.
- tssva 7y ago
  The article clearly states that the SpaceX satellite was at this position because they were deorbiting it under power.
- semi-extrinsic 7y ago
  Why are they deorbiting? Didn't they just launch these?
  - duskwuff 7y ago
    To test their ability to perform a controlled deorbit.
    - fwip 7y ago
      Sounds like the test didn't work, if they can't avoid hitting other satellites.
  - foobiekr 7y ago
    They are test satellites with no lateral switching capability.

rocqua 7y ago

I presume there are liability rules if your satellite hits another one. What about if your satellite makes another one waste fuel on a diversion?

avocado4 7y ago
Would ESA satellite hit Space X or the other way around? How do they determine it?
- jsiepkes 7y ago
  The ESA satellite had been on that orbit 9 months before the Spacelink satellite.
peteretep 7y ago
Where would have jurisdiction?
- mises 7y ago
  I could see them going after a european company, or America going after an American company. I'm guessing the europeans are going to insist they want it done in their courts, and SpaceX is just gonna shrug and say, "Nope, not showing up." europeans can't really make an American company do much.
  - peteretep 7y ago
    > europeans can't really make an American company do much There's very few large American companies for whom the EU is neither a huge market, nor a major location.
mlindner 7y ago
By international space law full liability is held by the country of launch/license. The US Government would owe the ESA a full paycheck if it was to be damaged. So this is already well covered in international law.

londons_explore 7y ago

The US military tracking isn't very accurate. Errors of hundreds of meters are common. I bet spacex themselves know the location of their satellites to within a few meters. With more accurate data, you can come up with a far more accurate collision risk estimate.

SiempreViernes 7y ago
Ok, so by which physical method do they have better telemetry?
- DuskStar 7y ago
  Active transponders on the satellite itself. GPS fixes. Other observations from the satellite. Controlling the target makes some problems a lot easier.
  - SiempreViernes 7y ago
    GPS appears to not give great online performance in LEO[1], and transponders is just slightly easier radar, not a fundamental difference. Do they have really good star trackers on their sats? [1]: https://space.stackexchange.com/questions/563/in-leo-what-is-the-precision-of-gnss-based-position-compared-to-traditional-met https://space.stackexchange.com/questions/563/in-leo-what-is...
    - dtkav 7y ago
      They don't need great online performance, they need offline performance for orbit determination. Once they have a good orbit fit, they will propagate it to predict the probability of collision a few days in advance.
- dtkav 7y ago
  gps (NORAD is using radar)
- debatem1 7y ago

areoform 7y ago

Being a lover of Space and SpaceX, this incident highlights why a goldilocks paradigm for regulation needs to exist for space. Not too much that it stifles innovation. Not too little that someone ends up Kesslerizing Near-Earth space. Current regulations are largely successful at promoting commercial space flight, but there is a big transparency gap between civilian space flight agencies and private entities. Transparency should be one of the cornerstones of space regulations, but it isn’t. This incident raises multiple policy questions. Why can’t SpaceX move their satellite? Is it a no because an ion drive takes days to burn or is it a no because they don’t wanna? Either way, it exposes a flaw in SpaceX’s design and raises concerns about StarLink. When there are hundreds of StarLink satellites in the air, will SpaceX say no again if there’s a chance for collision? Will SpaceX be a responsible steward of Near-Earth space? If ion drives are insufficient to address this problem, should they be required to take a small amount of monopropellant as a precaution? Transparency is essential for answering these questions and asking new ones. The one I’m most concerned about is the question, what are the pollution risks of LEO constellations? Ideally, before StarLink and other networks are up and running, I feel there should be a study of the pollution risk StarLink poses be it light pollution or debris. We shouldn’t repeat the failings of the 20th century in space.

deleted 7y ago
[deleted]
avocado4 7y ago
> Either way, it exposes a flaw in SpaceX’s design What is this statement based on? You are saying yourself that there's no information available to the public about this due to lack of transparency, yet in the next sentence you are making a bold statement about design flaws. To me it sounds like there should be clear regulation about right of way in space. I haven't seen any information pertaining to SpaceX design so far.
- dahdum 7y ago
  > To me it sounds like there should be clear regulation about right of way in space Common courtesy worldwide would be for the person causing the risk to move aside first. Worse still it was a private company working on a for-profit product forcing a public weather satellite to divert. There's no need for regulation until bad actors show up.

mabbo 7y ago

The ESA is sure making a huge deal out of this. I wonder if politics is involved. https://twitter.com/IridiumBoss/status/1168582141128650753 https://twitter.com/IridiumBoss/status/1168582141128650753 > Hmmm. We move our satellites on average once a week and don't put out a press release to say who we maneuvered around... -Matt Desch, CEO of Iridium

avocado4 7y ago
> In 2018, ESA performed 28 #collisionavoidance manoeuvres across its fleet.
- FireBeyond 7y ago
  ... typically of dead satellites or debris that is unable to move itself. ESA had a weather satellite in orbit, SpaceX actively moved an active satellite _into_ the same orbit as ESA's satellite (to practice maneuvers) and then said "no, we won't move it back out the way".
  - manicdee 7y ago
    No. All deorbiting objects (“satellites” or debris, whatever you want to call them) are going to pass through the orbit of the ESA satellite which is intentionally in a very low orbit. It is the ESA that actively moved into that orbit by design, intention and active navigation. SpaceX intended their satellite to lift to a higher orbit but it couldn’t make it, so it is being deorbited by atmospheric drag. All orbits at the same altitude will cross at least twice. This is not a deliberate act of interception but just part of the way orbits work.
    - FireBeyond 7y ago
      That article started that the Spacelink satellite -had- been at a much higher orbit (the "regular" for their satellites, but had been brought down "to test de-orbiting maneuvers". Do you have a source to the contrary? Also, the ESA satellite has been in that orbit for 8+ years. It wasn't "moved" into the Spacelink orbit by any means. I get that en route to or from orbit, entities will pass through other orbits.

mLuby 7y ago

>ESA noted that it performed 28 collision avoidance maneuvers in 2018, but it was mostly to avoid dead satellites or bits of space debris. Maneuvers to avoid active satellites were “very rare”, they said, but the arrival of mega constellations like Starlink raises concerns that many more such maneuvers will be needed in future. >“What I want is an organized way of doing space traffic. It must be clear when you have such a situation who has to react. And of course automating the system. It cannot be when we have 10,000 satellites in space that there are operators writing the email what to do. This is not how I imagine modern spaceflight.” SpaceX simply saying it would "not act" is negligent, and I really hope there was more to it that the author just wasn't privy to. If they had better sensors and knew there'd be no collision, say so. If they couldn't maneuver, say so. Otherwise it's just a game of space chicken, risking not only those two sats but all of LEO.

pergadad 7y ago
One is a throwaway satellite of a huge constellation - the other a unique billion euro research satellite. Easy to see who will give in first to protect their assets, but plainly it is equally easy to see who should move first.
- oh_sigh 7y ago
  What happens if the two groups disagree on the odds of impact? Because one has either more precise or just different telemetry than the other?
  - safsafasf 7y ago
    There's not much to disagree on the odds. Trajectories are known, uncertainties too and therefore probabilities of collisions can be calculated. Any disagreement here is easy to reconcile, whose assumptions and methods are more accurate? The disagreement is on the importance of the odds. SpaceX might be OK with a 1:10000 (or whatever) chance of collision, the Europeans want it lower. The Europeans could in the future force the issue. Move, or we'll fine you and forbid you from launching off of European sites and ban EU companies from using SpaceX.

everyone 7y ago

https://en.wikipedia.org/wiki/Kessler_syndrome https://en.wikipedia.org/wiki/Kessler_syndrome Yay!!

guerrilla 7y ago
Animated version: https://www.youtube.com/watch?v=yS1ibDImAYU https://www.youtube.com/watch?v=yS1ibDImAYU

Steel_Phoenix 7y ago

I was under the impression that most of the constellation would be at such an unusually low orbit that there wouldn't be much to collide with. How crowded are the planned orbit shells?

DreamSpinner 7y ago

What's interesting is that there's already a similar internationally agreed framework for how to approach this - shipping - https://en.wikipedia.org/wiki/International_Regulations_for_Preventing_Collisions_at_Sea https://en.wikipedia.org/wiki/International_Regulations_for_... - These would probably be a good place to start considering a framework for satellite orbit adjustments. However, despite this framework, it still happens - and I can see the issue of risk evaluation being a big one - what if one entity thinks a 1/1000 risk is acceptable for their cheap satellite vs the other satellite wanting 1/1000000?

pmyteh 7y ago
You're liable for damage to the other party if you're at fault for a maritime collision, so there's at least some countervailing economic pressure against taking the risk. Your insurers will not be happy with you if you negligently sink someone else's oil tanker.
frankharv 7y ago
I agree with this. Rules of the seas are not laws but more like a code for mariners to follow. Too bad we see such ignorance in space. Think of the ESA bird as a "boat in anchor". Lit up with the proper anchorage lights. Now some jackass with a jetski is blasting right twords you.

dmix 7y ago

> ESA is preparing to automate this process using #AI Sounds like something SpaceX and other constellation satellite companies should do as part of these widescale deployment. Or at least lower the threshold of moving out of the way so they don't get tons of push back from existing space power players who’ve got more influence than they do.

dzhiurgis 7y ago

Is there any right of way rules similar to how marine traffic works?

ricardobeat 7y ago

Judging by the comments here, this piece has succeeded in planting the idea that StarLink is dangerous using incredibly little detail.

asdff 7y ago
More like "Musk company does something arrogant again"

mises 7y ago

This is gonna get ugly pretty soon. I'm pretty convinced it's less an issue of moving (which esa itself stated it does once every week to two weeks) and more of politics. A couple possibilities: * europe mad at America b/c trade * europe mad at American companies beating european ones to space and getting more of the limited orbit spots first * europe mad she wasn't really asked before SpaceX put up satellites * europe has a principal objection to the idea of private companies playing on the same level as the bureaucrats or an issue with corps occupying space at all Most likely, it's a combination of all of the above. Regardless, people will start getting awfully catty about this, and it's possible knocking some one else's satellite out of the sky could be a serious issue.

zaroth 7y ago

NORAD 44278 is a Starlink satellite presently being de-orbited by SpaceX in a controlled fashion to simulate end-of-life disposal. [1] The current altitude (~330km) [2] puts it well below the operation envelope and it’s currently the lowest sat of the Starlink constellation at this point. It appears SpaceX does continue to have some level of control of the craft. [3] Some speculation I’ve read is that the much higher impulse of the ESA thrusters would make the ESA craft a better candidate to execute the maneuver. These adjustments are not rare - they happen approximately every other week for this particular craft, and as Iridium says, they do this weekly. [4] A video of the conjecture [5] shows an approach of “less than 10km”. The ESA craft apparently passed much closer to several other craft over the last week, so there may be more to it in this case, or there may be a bone to pick with Starlink. Lastly, ESA has a particular interest in raising this issue now as much as possible, as these “mega-constellations” launched by US companies are coming closer to reality and the current processes (picking up the phone) don’t scale well to tens of thousands of satellites. [1] - https://twitter.com/thesheetztweetz/status/1144689334777524226?s=21 https://twitter.com/thesheetztweetz/status/11446893347775242... [2] - https://www.n2yo.com/satellite/?s=44278 https://www.n2yo.com/satellite/?s=44278 [3] - https://twitter.com/planet4589/status/1168637324592328705?s=21 https://twitter.com/planet4589/status/1168637324592328705?s=... [4] - https://twitter.com/iridiumboss/status/1168582141128650753?s=21 https://twitter.com/iridiumboss/status/1168582141128650753?s... [5] - https://twitter.com/m_r_thomp/status/1168583891726344193?s=21 https://twitter.com/m_r_thomp/status/1168583891726344193?s=2...

manicdee 7y ago
The “more to it” is that ESA is gearing up to request funding for their AI project, billed as an automated tracking and avoidance manoeuvre planning system capable of handling the vast numbers of objects and debris expected to be in orbit in the near future. This was not about “SpaceX refused to move” but “we need money to build this automated system so we don’t have to do it all by hand,” and an additional level which is, how should the various satellite operators make their orbital parameters available to interested parties? The situation is that ESA didn’t even know what kind of object the track represented, and they had to contact SpaceX to ask about it in the first place. Their job would have been easier (whether manual or automated) if SpaceX made the orbital parameters available for automated queries. The last thing this is about is SpaceX being “arrogant” or “refusing to move a satellite.”

newnewpdro 7y ago

I guess when you have your own launch capabilities you can treat your internet satellites as easily replaced. Adding more junk up there only serves to create more launches as the inevitable collisions occur. It arguably makes good business sense for SpaceX to add as much as possible and be quite fast and loose with their management of it, at least as long as it's the wild west up there.

WalterBright 7y ago

The long term solution would be to establish some form of property rights over particular orbits. Then, to use a particular orbit, one must pay the market rate for it.

greglindahl 7y ago
Deorbiting satellites make that a hilarious proposal.
- WalterBright 7y ago
  Certainly property rights to orbits will have special characteristics. We've already accumulated much experience with property rights for things that are different from physical property - I'm sure spending more than 30 seconds thinking about it can come up with solutions.

mlindner 7y ago

This is a false article. There is no evidence SpaceX refused to move and ESA calling out the fact that they moved for a SpaceX satellite is ESA playing politics. LEO is full of space debris and satellite owners move satellites for space junk all the time. This is called political grandstanding.

mLuby 7y ago

"SpaceX, in a new statement, says they were aware of the potential Aeolus/Starlink collision, but at first the probability was low. When the probability increased, “a bug in our on-call paging system prevented the Starlink operator from seeing the follow on correspondence.”" https://twitter.com/jeff_foust/status/1168919094265044996 https://twitter.com/jeff_foust/status/1168919094265044996