So the main problem I see is a lot of miscommunication and a lack of cooperation between SpaceX and ESA.If SpaceX wants Starlink to be successfull they should really start to consider the concerns of the other players. There will be new rules in the future, just because the amount of new satellites is too big. And if you want these regulations be in favour of your plans, you need the others to trust you.So it should be in SpaceX own interest to have a better relation with ESA (and the scientific community in general) in the future.
Zuvor hatte die ESA SpaceX kontaktiert. Zusammen wurde entschieden, dass "Aeolus" ausweicht. Die Absprache sei wichtig, sagte Holger Krag, der Leiter des Esa-Büros für Raumfahrtrückstände. Ansonsten könnte es im schlimmsten Fall sein, dass beide Satelliten in die gleiche Richtung ausweichen und so weiter aufeinanderzusteuern. Die Absprache mit SpaceX funktionierte laut dem Experten gut. Das sei nicht immer so: "Es gibt Satellitenbetreiber, die reagieren gar nicht, wenn man sie anschreibt."
Quote from: Marci on 09/03/2019 04:26 pmSo the main problem I see is a lot of miscommunication and a lack of cooperation between SpaceX and ESA.If SpaceX wants Starlink to be successfull they should really start to consider the concerns of the other players. There will be new rules in the future, just because the amount of new satellites is too big. And if you want these regulations be in favour of your plans, you need the others to trust you.So it should be in SpaceX own interest to have a better relation with ESA (and the scientific community in general) in the future.In this instance I believe ESA could have handled this in a more professional manner. Twitter is not the venue to use for a general avoidance maneuver or to use this situation for other means without direct dialogue with those in a conflicting situation.oops...been ninja'd
Quote from: gongora on 09/03/2019 02:01 pmQuote from: su27k on 09/03/2019 01:51 pmThe SpaceNews article was updated to say ESA received notification 5 days before the close approach, presumably SpaceNews run SOCRATES after the ESA tweet which is yesterday, so the data used by SpaceNews' SOCRATES run should be only 2 days before the close approach at maximal, which is 3 days after the 5 days notification.Did you really read that article? Maybe you should read it again. It doesn't say anything about Space News running SOCRATES. It does say that ESA monitored the situation from the time they were informed of it and then made the decision to adjust the orbit the day before the potential conjuction. The idea that Space News somehow ran a better analysis of the situation than ESA is ridiculous.Of course I read it, twice, once before they did the update, once after they did the update. If SpaceNews didn't run SOCRATES, where did this comes from?QuoteAccording to a list of conjunctions called the Satellite Orbital Conjunction Reports Assessing Threatening Encounters in Space (SOCRATES), maintained by the Center for Space Standards & Innovation, Aeolus was predicted to have a close approach shortly after 7 a.m. Eastern Sept. 2 with a satellite identified as “Starlink AV” for its international designation, 2019-029AV. The two satellites were predicted to come within about four kilometers of each other, at a relative velocity of 14.4 kilometers per second. However, the SOCRATES data predicted a very low probability of collision — less than one in one million — which ordinarily would be far below the threshold for an avoidance maneuver.And where did I suggest SpaceNews' analysis is better? What I'd like to know is the cause of the different results, is it because 18SPCS public TLE data is not accurate? Or something else.And if public TLE data is not accurate, is it because 18SPCS is holding back more accurate dataset, or is it because ESA is not sharing up to date orbital data with 18SPCS? Both are concerning, especially given a few pages back some people are concerned the public TLE age is too old, but if 18SPCS has a secret dataset which it only shares with operators, then the age of the public TLE doesn't matter. It's all tied together, you can't argue both ways.
Quote from: su27k on 09/03/2019 01:51 pmThe SpaceNews article was updated to say ESA received notification 5 days before the close approach, presumably SpaceNews run SOCRATES after the ESA tweet which is yesterday, so the data used by SpaceNews' SOCRATES run should be only 2 days before the close approach at maximal, which is 3 days after the 5 days notification.Did you really read that article? Maybe you should read it again. It doesn't say anything about Space News running SOCRATES. It does say that ESA monitored the situation from the time they were informed of it and then made the decision to adjust the orbit the day before the potential conjuction. The idea that Space News somehow ran a better analysis of the situation than ESA is ridiculous.
The SpaceNews article was updated to say ESA received notification 5 days before the close approach, presumably SpaceNews run SOCRATES after the ESA tweet which is yesterday, so the data used by SpaceNews' SOCRATES run should be only 2 days before the close approach at maximal, which is 3 days after the 5 days notification.
According to a list of conjunctions called the Satellite Orbital Conjunction Reports Assessing Threatening Encounters in Space (SOCRATES), maintained by the Center for Space Standards & Innovation, Aeolus was predicted to have a close approach shortly after 7 a.m. Eastern Sept. 2 with a satellite identified as “Starlink AV” for its international designation, 2019-029AV. The two satellites were predicted to come within about four kilometers of each other, at a relative velocity of 14.4 kilometers per second. However, the SOCRATES data predicted a very low probability of collision — less than one in one million — which ordinarily would be far below the threshold for an avoidance maneuver.
Quote from: Draggendrop on 09/03/2019 04:42 pmQuote from: Marci on 09/03/2019 04:26 pmSo the main problem I see is a lot of miscommunication and a lack of cooperation between SpaceX and ESA.If SpaceX wants Starlink to be successfull they should really start to consider the concerns of the other players. There will be new rules in the future, just because the amount of new satellites is too big. And if you want these regulations be in favour of your plans, you need the others to trust you.So it should be in SpaceX own interest to have a better relation with ESA (and the scientific community in general) in the future.In this instance I believe ESA could have handled this in a more professional manner. Twitter is not the venue to use for a general avoidance maneuver or to use this situation for other means without direct dialogue with those in a conflicting situation.oops...been ninja'dESA went to twitter long after the maneuver had been performed. And they did have a direct dialog with SpaceX, per their statements to Forbes and SpaceNews.
Interview on "space safety" with ESA expert Holger Krag was just published by German quality daily (Frankfurter Allgemeine Zeitung):https://www.faz.net/aktuell/wissen/weltraum/esa-satellit-muss-musks-starlink-satellit-ausweichen-16366503.htmlIMHO, his statements are balanced and reasonable. No bashing that I can perceive. He argues that new procedures -- largely automated and autonomous -- need to be discussed and agreed upon, because such incidents are bound to become increasingly frequent.
A SpaceX spokesperson said a bug in its on-call operating system prevented the team from seeing that the risk of a collision with the ESA craft may have increased.“Had the Starlink operator seen the correspondence, we would have coordinated with ESA to determine best approach with their continuing with their manoeuvre or our performing a manoeuvre,” the spokesperson said.
By the way, who is responsible for warning SpaceX about collision threats? Is this the USAF? Do they provide this as a service to all satellite operators?
Quote from: aameise9 on 09/03/2019 06:54 pmInterview on "space safety" with ESA expert Holger Krag was just published by German quality daily (Frankfurter Allgemeine Zeitung):https://www.faz.net/aktuell/wissen/weltraum/esa-satellit-muss-musks-starlink-satellit-ausweichen-16366503.htmlIMHO, his statements are balanced and reasonable. No bashing that I can perceive. He argues that new procedures -- largely automated and autonomous -- need to be discussed and agreed upon, because such incidents are bound to become increasingly frequent.Did he discuss that ESA is seeking funding for just such a system?
I think that in the next two to three years we should have technical solutions that make our work much easier. Communication protocols, automatic decisions based on machine learning. Perhaps also the possibility of reaching the satellite at any time and not just when it is flying over a ground station, so that we can react more flexibly. Our proposal is to demonstrate by 2023 that a satellite makes a decision after a collision warning, votes and then evades autonomously. Autonomous does not mean that it does everything on board, which of course requires contact with the ground. But at the moment we are not in a position to do so. Many experts are paid to stay awake around the clock and assess the situation. And that is no longer manageable when we soon have five times the number of satellites.Translated with www.DeepL.com/Translator
Quote from: Draggendrop on 09/03/2019 04:42 pmQuote from: Marci on 09/03/2019 04:26 pmSo the main problem I see is a lot of miscommunication and a lack of cooperation between SpaceX and ESA.If SpaceX wants Starlink to be successfull they should really start to consider the concerns of the other players. There will be new rules in the future, just because the amount of new satellites is too big. And if you want these regulations be in favour of your plans, you need the others to trust you.So it should be in SpaceX own interest to have a better relation with ESA (and the scientific community in general) in the future.In this instance I believe ESA could have handled this in a more professional manner. Twitter is not the venue to use for a general avoidance maneuver or to use this situation for other means without direct dialogue with those in a conflicting situation.oops...been ninja'dTwitter was used to report the news after the event.SpaceX have admitted that they were partly at fault: QuoteA SpaceX spokesperson said a bug in its on-call operating system prevented the team from seeing that the risk of a collision with the ESA craft may have increased.“Had the Starlink operator seen the correspondence, we would have coordinated with ESA to determine best approach with their continuing with their manoeuvre or our performing a manoeuvre,” the spokesperson said.This is a bit like pulling out of a junction without seeing another car, with both having equal priority, but the other driver has plenty of time to avoid you, and does so. A quick "sorry" is the end of the problem.Except in this case .... some sort of procedures will be needed to support 10s of thousands of satellites in orbit. For everyone's sake. By the way, who is responsible for warning SpaceX about collision threats? Is this the USAF? Do they provide this as a service to all satellite operators?
I'm a little surprised this problem isn't far more tractable than it seems on the surface based on how the principals are behaving. Is there something that makes this anything other than a mathematics problem, even if that mathmatics problem requires an excessive number of FLOPS from the CPU hamsters?It almost feels like they are calculating 1in1000 because they are arbitrarily introducing an artificial "sphere of uncertainty" which turns something they know is a non-collision intersection into one that might have some marginal chance of collision.Seems strange. Curious if knowledgeable folk know differently.
Looking at the orbital parameters of Aeolus, the satellite it intercepted was 44278 aka 2019-029AV, currently in a 346km by 311km orbit (as of the last TLE), the only satellite with the perigee lower than the Aeolus mean orbital altitude, that currently is in a 314km by 308 km orbit.