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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.co

by 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.
      - manicdee 7y ago
        Deorbiting is exactly the process I was describing. SpaceX did not deliberately move their craft to interfere with Aeolus. Aeolus is deliberately placed where every deorbiting craft will interfere with it. It’s like someone setting up an office in the foyer of an apartment complex. Everyone entering or leaving the complex is going to walk through the office. They aren’t deliberately walking through the office, it’s just that your office is where everyone is walking to get to where they are going. In addition, SpaceX is testing deorbiting satellites with Hall effect thrusters that are barely powerful enough to raise orbit from higher in the atmosphere. At this altitude the thrusters would have little or no effect, so the craft is more or less an inert piece of space junk which SpaceX can possibly rotate using reaction wheels and magnetic torquers. Words have meanings, and there is a vast semantic gulf between “SpaceX refused to take action” and “SpaceX were incapable of taking action”. The author used “refused” but published the article before investigating further. Expect a better story to come from the likes of Loren Grush in a couple of days once people have had time to get a response from SpaceX and digest just what is going on here (NB: ESA budget under review in November, as per ESA’s entire tweet thread of which this social media shitstorm is only responding to the first because it mentions SpaceX) This is really just a semantic argument so I will leave it here. Reread the article but completely ignore the inflammatory clickbait title and any of the author’s own (emotive, inflammatory) words on the matter, stick to only the quotes from named sources and you should be golden.
    - safsafasf 7y ago
      " SpaceX intended their satellite to lift to a higher orbit but it couldn’t make it, so it is being deorbited by atmospheric drag." I don't understand this. If the satellite is being de-orbited, why bother pissing off the ESA to save fuel?
SiempreViernes 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." Basically they think SpaceX is driving recklessly, which is why they put out the press release; they don't do it when they dodge dead satellites.
dahdum 7y ago
SpaceX is planning to put 12,000 more satellites up, so their refusal to move to avoid a possible collision they caused is notable. They've also refused to comment, and Musk's reputation doesn't engender faith in their reasons.
- dzhiurgis 7y ago
  Perhaps not a bad plan if you want to destroy everyone elses but USA’s sats
  - javagram 7y ago
    A collision would result in 1000s of pieces of debris that would affect everyone’s satellites. Repeated collision would make these orbits unusable until gravity and atmospheric drag naturally deorbit the fragments.
    - dzhiurgis 7y ago
      afaik thats not really long time
      - kakwa_ 7y ago
        "Not a very long time" is pretty vague. Also, even if the impact is limited in term of long lasting debris, losing several satellites, and as a consequence losing the services they provide plus having to replace them is definitely a large impact which will last years.
        yreg 7y ago
        When it happens we will have to cease all launches for a few years, until the sky clears out. That would certainly be terrible, but not ice-caps-melting-terrible.
      - dwaltrip 7y ago
        A lot of space debris doesn't have very much drag (imagine a small round chunk of metal) and can taken tens of years or longer to de-orbit. So this approach won't work.
lukeschlather 7y ago
The ESA asked SpaceX to move to avoid a collision, and they refused. What would happen if a private airline refused the FAA telling them to redirect to avoid a collision, forcing another aircraft to take evasive action? It definitely is political, and it's going to become a bigger problem if SpaceX's approach to potential collisions is just to play chicken.
- mikeash 7y ago
  The ESA isnt a governing authority here. The proper analogy would be two planes in uncontrolled airspace on course to come uncomfortably close. One asks the other to change course, and the other refuses. No FAA involved. This sort of thing actually happens with some regularity. Airliners and other fancy planes carry TCAS systems which can detect other planes and tell the pilot to maneuver to avoid a collision. If the other plane has TCAS, the two units will coordinate to ensure they don’t both dodge the same way. TCAS can also detect planes that don’t have TCAS, which would be virtually all small planes, and in that instance the TCAS-equipped plane will maneuver to avoid on its own. Airliners routinely fly though airspace where not all traffic is under positive control by ATC. Sometimes they end up on a course that sets off TCAS. The airliner will then maneuver to avoid the collision while the light aircraft pilot remains blissfully unaware, unless they happen to see the airliner fly past.
  - throw0101a 7y ago
    > The ESA isnt a governing authority here. You're not wrong, but annoying the folks that may be involved in regulatory approval for your venture to get commercially licensed is not prudent.
    - dahdum 7y ago
      It’s Musk, playing stupid games for stupid prizes seems to be his favorite hobby.
- manicdee 7y ago
  The bigger issue is that ESA is coming up to an important administrative date in November where their future budget will be determined, and they want money for their automation program. So they have to portray space as dangerous, ESA processes as desperately in need of improvement, and this specific example of a super expensive research satellite coming close to part of a future megaconstellation makes for great attention-grabbing headlines. That it was SpaceX that ESA got to throw under the bus was the cherry on the cake.
Rapzid 7y ago
It reads almost like the Musk hit pieces typically delivered under the cover of op-eds.. "Blue, we are uncomfortable with the possibility of collision on our current courses, requesting you adjust course 5 degrees starboard." "Nah Red, looking all good here." "Okay, we will move." - Every 5 minutes on the water probably
- _visgean 7y ago
  > "Nah Red, looking all good here." more like "nah." spacex did not inform ESA that the risk is lower or anything like that.
  - asdfasgasdgasdg 7y ago
    I don't see where it positively states that SpaceX provided no reasoning. In my reading of the article, Krag did not speak directly with SpaceX. SpaceX were alerted to the possibility of collision by the U.S. military, and nobody who was party to that conversation is quoted in the article. All we know for sure is that SpaceX did not proactively reach out to the Space Debris Office at the ESA about this issue, at least as of the time the interview with Krag occurred (which would not have been more than a few hours after the incident to get this blog post written and published by 4PM ET given the incident occurred at 7AM ET).
  - Rapzid 7y ago
    We don't know the extent of the communication from this article.
- javagram 7y ago
  The article explains the ESA is raising this issue because there is no such mechanism to perform “every 5 minutes” avoidance maneuvers right now. The current process is manual and slow. 22,000 satellites in that orbit mean that picking up the telephone to call each other to say “hey are you going to move your satellite to avoid X possible collision on Y date?” isn’t going to scale, so they’re saying that a better system needs to be put in place. We’ve seen just recently with multiple US Navy collisions causing loss of life that using “common sense” to avoid collisions instead of being prepared and planning doesn’t always work out well..
sdinsn 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. The reason why it's a big deal is that SpaceX is planning on putting up a LOT more.
- HarryHirsch 7y ago
  The reason why it's a big deal is that SpaceX is planning on putting up a LOT more On one side is a multimillion-dollar weather satellite, on the other side 1536 throwaway satellites, 5 % of which failed during commissioning (the track record of the initial batch gives you an idea what to expect for the future). It's easy to see who will move their asset out of the way and also easy to see who has no business being up there.
  - manicdee 7y ago
    The track record of experimental designs deliberately intended to push the boundaries of reliability really does not give us any idea of what to expect for the future.
    - HarryHirsch 7y ago
      Spacecraft engineering is inherently conservative because of reliability concerns, you can't take a tow truck and mechanic in orbit to fix things when it turns out that you didn't understand the latest technology quite as well as you thought. Space isn't the place to push technical boundaries, also because of orbital littering.
      - adventured 7y ago
        > Space isn't the place to push technical boundaries Fortunately space, for over half a century, has routinely been the place to push all manner of technical boundaries.
      - manicdee 7y ago
        The inability to take a tow truck to orbit is exactly why you need to push the boundaries to find out what works and what doesn’t. Also note that “littering” is an irrelevant analogy in these orbits because of their low altitude. Atmospheric drag will cause anything in these orbits to deorbit in a matter of years to decades. Just don’t go doing stupid stuff like releasing hundreds of millions of copper needles in a three-thousand-kilometre orbit as part of a misguided attempt to provide a reflective surface to carry military communications around the globe. That would be actual littering, as would any test of an anti-satellite weapon.
optimiz3 7y ago
The Forbes title frames a bit of bias too. An equally valid title would be "ESA Initially Refused to Move Satellite at Risk of Collission with a SpaceX Satellite".
yreg 7y ago
He also continues >Normal part of flying satellites (or should be). Does BA announce every time one of its airplanes steers around a Ryanair aircraft?
- DoctorOetker 7y ago
  airplanes will refuel when they land, satellites have limited propellant, so it really is a game of chicken or dare!
  - yreg 7y ago
    I don't understand the matter first hand, but I believe this comment I read on reddit today: The % of fuel used in this type of maneuver is negligible. A sat in LEO like this uses fuel to: - correct their orbit from the initial release from the rocket - maintain orbit - deorbit - avoidance The breakdown is something like: 66%, 33.5%, 0.45%, 0.05% The ESA sat in this case boosted their sat... which they planned on doing anyways. So it probably cost close to nothing. It maybe reduced the lifespan of the sat by 0.001% https://www.reddit.com/r/spacex/comments/cypvjv/this_morning_esas_aeolus_earth_observation/eyuoo9u/ https://www.reddit.com/r/spacex/comments/cypvjv/this_morning...
    - DoctorOetker 7y ago
      it's a matter of precedent, it's much harder to change rules and agreements when multiple stakeholders have planned on an assumed state of laissez faire, compared to learning from the first "conflicts".

by mabbo 7y ago

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.
    - manicdee 7y ago
      Deorbiting is exactly the process I was describing. SpaceX did not deliberately move their craft to interfere with Aeolus. Aeolus is deliberately placed where every deorbiting craft will interfere with it. It’s like someone setting up an office in the foyer of an apartment complex. Everyone entering or leaving the complex is going to walk through the office. They aren’t deliberately walking through the office, it’s just that your office is where everyone is walking to get to where they are going. In addition, SpaceX is testing deorbiting satellites with Hall effect thrusters that are barely powerful enough to raise orbit from higher in the atmosphere. At this altitude the thrusters would have little or no effect, so the craft is more or less an inert piece of space junk which SpaceX can possibly rotate using reaction wheels and magnetic torquers. Words have meanings, and there is a vast semantic gulf between “SpaceX refused to take action” and “SpaceX were incapable of taking action”. The author used “refused” but published the article before investigating further. Expect a better story to come from the likes of Loren Grush in a couple of days once people have had time to get a response from SpaceX and digest just what is going on here (NB: ESA budget under review in November, as per ESA’s entire tweet thread of which this social media shitstorm is only responding to the first because it mentions SpaceX) This is really just a semantic argument so I will leave it here. Reread the article but completely ignore the inflammatory clickbait title and any of the author’s own (emotive, inflammatory) words on the matter, stick to only the quotes from named sources and you should be golden.
  - safsafasf 7y ago
    " SpaceX intended their satellite to lift to a higher orbit but it couldn’t make it, so it is being deorbited by atmospheric drag." I don't understand this. If the satellite is being de-orbited, why bother pissing off the ESA to save fuel?

SiempreViernes 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." Basically they think SpaceX is driving recklessly, which is why they put out the press release; they don't do it when they dodge dead satellites.

dahdum 7y ago

SpaceX is planning to put 12,000 more satellites up, so their refusal to move to avoid a possible collision they caused is notable. They've also refused to comment, and Musk's reputation doesn't engender faith in their reasons.

dzhiurgis 7y ago
Perhaps not a bad plan if you want to destroy everyone elses but USA’s sats
- javagram 7y ago
  A collision would result in 1000s of pieces of debris that would affect everyone’s satellites. Repeated collision would make these orbits unusable until gravity and atmospheric drag naturally deorbit the fragments.
  - dzhiurgis 7y ago
    afaik thats not really long time
    - kakwa_ 7y ago
      "Not a very long time" is pretty vague. Also, even if the impact is limited in term of long lasting debris, losing several satellites, and as a consequence losing the services they provide plus having to replace them is definitely a large impact which will last years.
      - yreg 7y ago
        When it happens we will have to cease all launches for a few years, until the sky clears out. That would certainly be terrible, but not ice-caps-melting-terrible.
    - dwaltrip 7y ago
      A lot of space debris doesn't have very much drag (imagine a small round chunk of metal) and can taken tens of years or longer to de-orbit. So this approach won't work.

lukeschlather 7y ago

The ESA asked SpaceX to move to avoid a collision, and they refused. What would happen if a private airline refused the FAA telling them to redirect to avoid a collision, forcing another aircraft to take evasive action? It definitely is political, and it's going to become a bigger problem if SpaceX's approach to potential collisions is just to play chicken.

mikeash 7y ago
The ESA isnt a governing authority here. The proper analogy would be two planes in uncontrolled airspace on course to come uncomfortably close. One asks the other to change course, and the other refuses. No FAA involved. This sort of thing actually happens with some regularity. Airliners and other fancy planes carry TCAS systems which can detect other planes and tell the pilot to maneuver to avoid a collision. If the other plane has TCAS, the two units will coordinate to ensure they don’t both dodge the same way. TCAS can also detect planes that don’t have TCAS, which would be virtually all small planes, and in that instance the TCAS-equipped plane will maneuver to avoid on its own. Airliners routinely fly though airspace where not all traffic is under positive control by ATC. Sometimes they end up on a course that sets off TCAS. The airliner will then maneuver to avoid the collision while the light aircraft pilot remains blissfully unaware, unless they happen to see the airliner fly past.
- throw0101a 7y ago
  > The ESA isnt a governing authority here. You're not wrong, but annoying the folks that may be involved in regulatory approval for your venture to get commercially licensed is not prudent.
  - dahdum 7y ago
    It’s Musk, playing stupid games for stupid prizes seems to be his favorite hobby.
manicdee 7y ago
The bigger issue is that ESA is coming up to an important administrative date in November where their future budget will be determined, and they want money for their automation program. So they have to portray space as dangerous, ESA processes as desperately in need of improvement, and this specific example of a super expensive research satellite coming close to part of a future megaconstellation makes for great attention-grabbing headlines. That it was SpaceX that ESA got to throw under the bus was the cherry on the cake.

Rapzid 7y ago

It reads almost like the Musk hit pieces typically delivered under the cover of op-eds.. "Blue, we are uncomfortable with the possibility of collision on our current courses, requesting you adjust course 5 degrees starboard." "Nah Red, looking all good here." "Okay, we will move." - Every 5 minutes on the water probably

_visgean 7y ago
> "Nah Red, looking all good here." more like "nah." spacex did not inform ESA that the risk is lower or anything like that.
- asdfasgasdgasdg 7y ago
  I don't see where it positively states that SpaceX provided no reasoning. In my reading of the article, Krag did not speak directly with SpaceX. SpaceX were alerted to the possibility of collision by the U.S. military, and nobody who was party to that conversation is quoted in the article. All we know for sure is that SpaceX did not proactively reach out to the Space Debris Office at the ESA about this issue, at least as of the time the interview with Krag occurred (which would not have been more than a few hours after the incident to get this blog post written and published by 4PM ET given the incident occurred at 7AM ET).
- Rapzid 7y ago
  We don't know the extent of the communication from this article.
javagram 7y ago
The article explains the ESA is raising this issue because there is no such mechanism to perform “every 5 minutes” avoidance maneuvers right now. The current process is manual and slow. 22,000 satellites in that orbit mean that picking up the telephone to call each other to say “hey are you going to move your satellite to avoid X possible collision on Y date?” isn’t going to scale, so they’re saying that a better system needs to be put in place. We’ve seen just recently with multiple US Navy collisions causing loss of life that using “common sense” to avoid collisions instead of being prepared and planning doesn’t always work out well..

sdinsn 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. The reason why it's a big deal is that SpaceX is planning on putting up a LOT more.

HarryHirsch 7y ago
The reason why it's a big deal is that SpaceX is planning on putting up a LOT more On one side is a multimillion-dollar weather satellite, on the other side 1536 throwaway satellites, 5 % of which failed during commissioning (the track record of the initial batch gives you an idea what to expect for the future). It's easy to see who will move their asset out of the way and also easy to see who has no business being up there.
- manicdee 7y ago
  The track record of experimental designs deliberately intended to push the boundaries of reliability really does not give us any idea of what to expect for the future.
  - HarryHirsch 7y ago
    Spacecraft engineering is inherently conservative because of reliability concerns, you can't take a tow truck and mechanic in orbit to fix things when it turns out that you didn't understand the latest technology quite as well as you thought. Space isn't the place to push technical boundaries, also because of orbital littering.
    - adventured 7y ago
      > Space isn't the place to push technical boundaries Fortunately space, for over half a century, has routinely been the place to push all manner of technical boundaries.
    - manicdee 7y ago
      The inability to take a tow truck to orbit is exactly why you need to push the boundaries to find out what works and what doesn’t. Also note that “littering” is an irrelevant analogy in these orbits because of their low altitude. Atmospheric drag will cause anything in these orbits to deorbit in a matter of years to decades. Just don’t go doing stupid stuff like releasing hundreds of millions of copper needles in a three-thousand-kilometre orbit as part of a misguided attempt to provide a reflective surface to carry military communications around the globe. That would be actual littering, as would any test of an anti-satellite weapon.

optimiz3 7y ago

The Forbes title frames a bit of bias too. An equally valid title would be "ESA Initially Refused to Move Satellite at Risk of Collission with a SpaceX Satellite".

yreg 7y ago

He also continues >Normal part of flying satellites (or should be). Does BA announce every time one of its airplanes steers around a Ryanair aircraft?

DoctorOetker 7y ago
airplanes will refuel when they land, satellites have limited propellant, so it really is a game of chicken or dare!
- yreg 7y ago
  I don't understand the matter first hand, but I believe this comment I read on reddit today: The % of fuel used in this type of maneuver is negligible. A sat in LEO like this uses fuel to: - correct their orbit from the initial release from the rocket - maintain orbit - deorbit - avoidance The breakdown is something like: 66%, 33.5%, 0.45%, 0.05% The ESA sat in this case boosted their sat... which they planned on doing anyways. So it probably cost close to nothing. It maybe reduced the lifespan of the sat by 0.001% https://www.reddit.com/r/spacex/comments/cypvjv/this_morning_esas_aeolus_earth_observation/eyuoo9u/ https://www.reddit.com/r/spacex/comments/cypvjv/this_morning...
  - DoctorOetker 7y ago
    it's a matter of precedent, it's much harder to change rules and agreements when multiple stakeholders have planned on an assumed state of laissez faire, compared to learning from the first "conflicts".