16 votes

SpaceX refused to move their Starlink satellite when they were alerted to the risk of collision with ESA's Aeolus satellite

14 comments

  1. [2]
    unknown user
    Link
    For those unaware, today, ESA had to perform an avoidance maneuver with one of their satellites operating in Low Earth Orbit to avoid a collision. Here's the tweet thread on that. Normally, this...

    For those unaware, today, ESA had to perform an avoidance maneuver with one of their satellites operating in Low Earth Orbit to avoid a collision. Here's the tweet thread on that. Normally, this is a non-event, but this was the first case where the object involved was from a up and coming internet mega constellation: SpaceX's Starlink.

    What now appears to be the case is that ESA engaged with SpaceX, who refused to move their satellite. This brings to the fore many issues concerning spaceflight 'right of way', being a tidy citizen of earth orbit, and how companies and governments may need to better work together to solve issues like these going forward.

    In my view, ESA should send SpaceX the bill, if this tweet is true.

    10 votes
    1. [2]
      Comment deleted by author
      Link Parent
      1. unknown user
        Link Parent
        I think there must be more behind this than what is presented by ESA, and I expect sometime soon Elon will provide some tenuously-truthful statements on Twitter that paint ESA as completely in the...

        I think there must be more behind this than what is presented by ESA, and I expect sometime soon Elon will provide some tenuously-truthful statements on Twitter that paint ESA as completely in the wrong and SpaceX as completely in the right. Not that I'd trust what Elon says anyway.

        Either way, it isn't a good look for SpaceX, they promised to be a responsible citizen in low earth orbit and they're off to a very bad start.

        Don't get me wrong, I'm enthused by what SpaceX is doing too, but I tend to adopt a Gruber-esque position when it comes to enjoying what a company does: praise them immensely for their successes, but don't hold back when they do fuck up, because they will—and defending the indefensible only emboldens corporate negligence and other anti-consumer/anti-environment decisions.

        NB My understanding is that onboard propulsion on the Starlink sats is provided by Krypton, not Xenon.

        10 votes
  2. [4]
    godless
    Link
    Reports are that there was a 1 in 1000 chance of collision, which is an order of magnitude lower than required to warrant needing to move the satellite. This coupled with this recent tweet from...

    Reports are that there was a 1 in 1000 chance of collision, which is an order of magnitude lower than required to warrant needing to move the satellite.

    This coupled with this recent tweet from Matt Desch, the CEO of Iridium satellites:
    @IridiumBoss: "Hmmm. We move our satellites on average once a week and don't put out a press release to say who we maneuvered around..."

    Makes me think this is nothing but noise being generated by the ESA

    7 votes
    1. [3]
      unknown user
      Link Parent
      No, in fact that's 10x higher than ESA's organizational requirement for altering a satellite's orbit: Matt's argument is reductive at best—the reason this was important was because it was a...

      No, in fact that's 10x higher than ESA's organizational requirement for altering a satellite's orbit:

      According to Holger Krag, head of the Space Debris Office at ESA, the risk of collision between the two satellites was 1 in 1,000 – ten times higher than the threshold that requires a collision avoidance maneuver.

      Matt's argument is reductive at best—the reason this was important was because it was a confluence of nuanced factors. That the satellite was being actively deorbited, SpaceX refused to engage with the ESA on helping to avoid a collision, and it's the first avoidance maneuver performed against a satellite that was part of a corporate mega-constellation, a competitor to Iridium's constellation that—ironically—Matt & Iridium helped finance.

      16 votes
      1. [2]
        godless
        Link Parent
        Unless we hear from an independent source, we won't know what the risk or distance apart they were. It could be that the starlink satellite telemetry is more accurate and SpaceX didn't think it...

        Unless we hear from an independent source, we won't know what the risk or distance apart they were. It could be that the starlink satellite telemetry is more accurate and SpaceX didn't think it required any further action. It could also be that they believe that the autonomous collision avoidance they have built in was sufficient to mitigate any risk.

        With Iridium I don't believe they are direct competitors. They are aiming for different markets and there is definitely room for both.

        I do agree however that it does bring up an interesting topic, with the rise of mega-constellations (and I think everyone will agree, starlink is not the first, nor will it be the last) - there isn't really a body that governs who can be in what orbit, a space traffic controller if you will.

        3 votes
        1. unknown user
          Link Parent
          But this would still demonstrate SpaceX was negligent by not providing the data into the public repository of TLEs for other satellite operators to gain insight from. It's not at SpaceX's sole...

          It could be that the starlink satellite telemetry is more accurate and SpaceX didn't think it required any further action.

          But this would still demonstrate SpaceX was negligent by not providing the data into the public repository of TLEs for other satellite operators to gain insight from. It's not at SpaceX's sole discretion about whether or not they think further action is warranted when you have a situation involving two satellite operators. Data sharing is crucial to ensuring that a common environment is kept safe—just like how you put your blinker on when making a turn. If you leave it off, sure, someone else may not hit you, but you're still negligent in communicating your action.

          It could also be that they believe that the autonomous collision avoidance they have built in was sufficient to mitigate any risk.

          This "autonomous collision avoidance" functionality doesn't actually exist and isn't integrated into the satellites at all. It's merely an aspirational goal.

          8 votes
  3. [4]
    spit-evil-olive-tips
    Link
    SpaceX is now claiming the lack of communication was caused by a bug in their on-call system:

    SpaceX is now claiming the lack of communication was caused by a bug in their on-call system:

    “Our Starlink team last exchanged an email with the Aeolus operations team on August 28, when the probability of collision was only in the 2.2e-5 range (or 1 in 50k), well below the 1e-4 (or 1 in 10k) industry standard threshold and 75 times lower than the final estimate. At that point, both SpaceX and ESA determined a maneuver was not necessary.

    “Then, the U.S. Air Force’s updates showed the probability increased to 1.69e-3 (or more than 1 in 10k) but a bug in our on-call paging system prevented the Starlink operator from seeing the follow-on correspondence on this probability increase – SpaceX is still investigating the issue and will implement corrective actions. However, had the Starlink operator seen the correspondence, we would have coordinated with ESA to determine best approach with their continuing with their maneuver or our performing a maneuver.”

    6 votes
    1. [3]
      JakeTheDog
      Link Parent
      Surely something like a phone-call would have been warranted? If it was an emergency like the ESA has made it out to be, you would expect that they would be pinging SpaceX in all the ways they can.

      Surely something like a phone-call would have been warranted? If it was an emergency like the ESA has made it out to be, you would expect that they would be pinging SpaceX in all the ways they can.

      5 votes
      1. [2]
        unknown user
        Link Parent
        The same could be said of SpaceX: surely they should have their systems working & in place, and should have followed up with the ESA when they didn't hear anything from them. Frankly I don't...

        The same could be said of SpaceX: surely they should have their systems working & in place, and should have followed up with the ESA when they didn't hear anything from them. Frankly I don't believe what SpaceX is saying here at all. It sounds like a very half-hearted excuse of "the dog ate my homework".

        Also, clever use of scientific notation to obfuscate the collision probability: 1.69e-3 is 1 in 571, which is a significant risk. This also clearly shows their autonomous collision avoidance software is not in place.

        10 votes
        1. JakeTheDog
          Link Parent
          Hey, I'm not defending SpaceX here. This is all smells of unprofessional conduct on both sides - though both are obviously staffed with extremely competent people.

          Hey, I'm not defending SpaceX here. This is all smells of unprofessional conduct on both sides - though both are obviously staffed with extremely competent people.

          3 votes
  4. sqew
    Link
    One interesting thing I saw on Twitter from one of the people I get most of my satellite tracking/TLE info from is that, since SpaceX are apparently currently deorbiting the satellite, there could...

    One interesting thing I saw on Twitter from one of the people I get most of my satellite tracking/TLE info from is that, since SpaceX are apparently currently deorbiting the satellite, there could be a huge margin of error in the TLEs that ESA were using.

    As a result of that possibility and the fact that we haven't heard from SpaceX about this at all, I'm currently withholding my judgement until we hear directly from them about what happened (especially since we have no actual context on what the SpaceX reply to the ESA actual said).

    5 votes
  5. JakeTheDog
    Link
    A bunch of commenters are saying that this isn't that big of a deal since it's a normal part of maintenance? I wonder if there is more to the story than simply SpaceX playing chicken with the ESA...

    A bunch of commenters are saying that this isn't that big of a deal since it's a normal part of maintenance? I wonder if there is more to the story than simply SpaceX playing chicken with the ESA (since that is a major lose-lose situation if things go wrong).

    2 votes
  6. [2]
    Comment deleted by author
    Link
    1. Deimos
      Link Parent
      Updated, thanks.

      Updated, thanks.

      4 votes