[Starlink] orbital maneuvers 12 per sat in the last 6 months

[Starlink] orbital maneuvers 12 per sat in the last 6 months

[Dave Taht]

https://www.space.com/starlink-satellite-conjunction-increase-threatens-space-sustainability

I am under the impression that each sat is capable of about 500 over
the satellite's lifetime. I am curious as to what they are avoiding.
-- 
Podcast: https://www.linkedin.com/feed/update/urn:li:activity:7058793910227111937/
Dave Täht CSO, LibreQos

Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months

[Daniel AJ Sokolov]

On 7/6/23 17:54, Dave Taht via Starlink wrote:
> https://www.space.com/starlink-satellite-conjunction-increase-threatens-space-sustainability
> 
> I am under the impression that each sat is capable of about 500 over
> the satellite's lifetime. I am curious as to what they are avoiding.

Assuming your number of 500 is correct, I don't see any worry here. 12 
moves in 6 months makes 492 in 20.5 years. That is less than 500 and 
beyond the lifetime expectation of the satellite anyway.

A I missing something?
Daniel AJ

Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months

[David Lang]

some people are assuming that more satellites launched will mean more maneuvers 
needed (not recognizing that what matters is only the things at the same 
altitude)

plus, it's a scary large number :-)

David Lang

  On Thu, 6 Jul 2023, Daniel AJ Sokolov via Starlink wrote:

> On 7/6/23 17:54, Dave Taht via Starlink wrote:
>> 
> https://www.space.com/starlink-satellite-conjunction-increase-threatens-space-sustainability
>> 
>> I am under the impression that each sat is capable of about 500 over
>> the satellite's lifetime. I am curious as to what they are avoiding.
>
> Assuming your number of 500 is correct, I don't see any worry here. 12 
> moves in 6 months makes 492 in 20.5 years. That is less than 500 and 
> beyond the lifetime expectation of the satellite anyway.
>
> A I missing something?
> Daniel AJ
> _______________________________________________
> Starlink mailing list
> Starlink@lists.bufferbloat.net
> https://lists.bufferbloat.net/listinfo/starlink
>

Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months

[blakangel]

I think the main point of the article is that the amount of maneuvers 
needed is currently increasing exponentially: "It's been doubling every 
six months, and the problem with exponential trends is that they get to 
very large numbers very quickly." I'm wondering if they are not taking 
into account the massive amount of satellites that have been launched 
since the previous six month report.

I found the semi-annual reports filed w/ the fcc: 
https://licensing.fcc.gov/myibfs/download.do?attachment_key=23204343 and 
https://licensing.fcc.gov/myibfs/download.do?attachment_key=23204338 for 
gen 1 and gen 2 constellations.

Still reading them and haven't found the older ones yet to compare.


David Lang via Starlink wrote on 7/6/2023 9:49 PM:

> some people are assuming that more satellites launched will mean more 
> maneuvers needed (not recognizing that what matters is only the things 
> at the same altitude)
>
> plus, it's a scary large number :-)
>
> David Lang
>
>  On Thu, 6 Jul 2023, Daniel AJ Sokolov via Starlink wrote:
>
>> On 7/6/23 17:54, Dave Taht via Starlink wrote:
>>>
>> https://www.space.com/starlink-satellite-conjunction-increase-threatens-space-sustainability 
>>
>>>
>>> I am under the impression that each sat is capable of about 500 over
>>> the satellite's lifetime. I am curious as to what they are avoiding.
>>
>> Assuming your number of 500 is correct, I don't see any worry here. 
>> 12 moves in 6 months makes 492 in 20.5 years. That is less than 500 
>> and beyond the lifetime expectation of the satellite anyway.
>>
>> A I missing something?
>> Daniel AJ
>> _______________________________________________
>> Starlink mailing list
>> Starlink@lists.bufferbloat.net
>> https://lists.bufferbloat.net/listinfo/starlink
>>
> _______________________________________________
> Starlink mailing list
> Starlink@lists.bufferbloat.net
> https://lists.bufferbloat.net/listinfo/starlink

Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months

[David Lang]

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they have been filling shells (altitude sets), so it makes sense for the numbers 
to have been going up.

we'll have to see if they keep going up as much as they move on to different 
altitude shells.

David Lang

On Thu, 6 Jul 2023, blakangel@gmail.com wrote:

> I think the main point of the article is that the amount of maneuvers needed 
> is currently increasing exponentially: "It's been doubling every six months, 
> and the problem with exponential trends is that they get to very large 
> numbers very quickly." I'm wondering if they are not taking into account the 
> massive amount of satellites that have been launched since the previous six 
> month report.
>
> I found the semi-annual reports filed w/ the fcc: 
> https://licensing.fcc.gov/myibfs/download.do?attachment_key=23204343 and 
> https://licensing.fcc.gov/myibfs/download.do?attachment_key=23204338 for gen 
> 1 and gen 2 constellations.
>
> Still reading them and haven't found the older ones yet to compare.
>
>
> David Lang via Starlink wrote on 7/6/2023 9:49 PM:
>
>> some people are assuming that more satellites launched will mean more 
>> maneuvers needed (not recognizing that what matters is only the things at 
>> the same altitude)
>> 
>> plus, it's a scary large number :-)
>> 
>> David Lang
>> 
>>  On Thu, 6 Jul 2023, Daniel AJ Sokolov via Starlink wrote:
>> 
>>> On 7/6/23 17:54, Dave Taht via Starlink wrote:
>>>> 
>>> https://www.space.com/starlink-satellite-conjunction-increase-threatens-space-sustainability 
>>>> 
>>>> I am under the impression that each sat is capable of about 500 over
>>>> the satellite's lifetime. I am curious as to what they are avoiding.
>>> 
>>> Assuming your number of 500 is correct, I don't see any worry here. 12 
>>> moves in 6 months makes 492 in 20.5 years. That is less than 500 and 
>>> beyond the lifetime expectation of the satellite anyway.
>>> 
>>> A I missing something?
>>> Daniel AJ
>>> _______________________________________________
>>> Starlink mailing list
>>> Starlink@lists.bufferbloat.net
>>> https://lists.bufferbloat.net/listinfo/starlink
>>> 
>> _______________________________________________
>> Starlink mailing list
>> Starlink@lists.bufferbloat.net
>> https://lists.bufferbloat.net/listinfo/starlink
>
>

Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months

[Daniel AJ Sokolov]

On 7/6/23 22:28, blakangel@gmail.com wrote:
> I think the main point of the article is that the amount of maneuvers 
> needed is currently increasing exponentially:

Indeed, I read that. But the article does not explain why they think 
this trend will continue exponentially.

Obviously it can't continue exponentially forever, because eventually 
all satellites are on the move evading one another 100% of the time. :-)

Cheers
Daniel

Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months

[Mike Puchol]

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Profession Hugh Lewis follows Starlink’s conjuction reports closely, and writes very detailed threads whenever a report comes up:

https://twitter.com/ProfHughLewis

Latest thread:

https://twitter.com/ProfHughLewis/status/1658173801924812803

If you want an idea of -what- they are avoiding, LeoLabs operates a set of radars which track anything larger than 10cm in cross-section, and provides an awesome visualization here:

https://platform.leolabs.space/visualization

(make sure to enable the “debris” checkbox too)

Best,

Mike
On Jul 7, 2023 at 08:23 +0200, Daniel AJ Sokolov via Starlink <starlink@lists.bufferbloat.net>, wrote:
>
> On 7/6/23 22:28, blakangel@gmail.com wrote:
> > I think the main point of the article is that the amount of maneuvers
> > needed is currently increasing exponentially:
>
> Indeed, I read that. But the article does not explain why they think
> this trend will continue exponentially.
>
> Obviously it can't continue exponentially forever, because eventually
> all satellites are on the move evading one another 100% of the time. :-)
>
> Cheers
> Daniel
> _______________________________________________
> Starlink mailing list
> Starlink@lists.bufferbloat.net
> https://lists.bufferbloat.net/listinfo/starlink

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Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months

[Daniel AJ Sokolov]

On 7/6/23 23:34, Mike Puchol via Starlink wrote:
> Profession Hugh Lewis follows Starlink’s conjuction reports closely, and writes very detailed threads whenever a report comes up:
> 
> https://twitter.com/ProfHughLewis
> 
> Latest thread:
> 
> https://twitter.com/ProfHughLewis/status/1658173801924812803

Unfortunately, Twitter-threads are no longer public.

BR
Daniel AJ

Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months

[Mike Puchol]

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Ah, yes… there is an article here which references Lewis and the latest report:

https://www.space.com/starlink-satellite-conjunction-increase-threatens-space-sustainability

Best,

Mike
On Jul 7, 2023 at 09:13 +0200, Daniel AJ Sokolov via Starlink <starlink@lists.bufferbloat.net>, wrote:
>
>
> On 7/6/23 23:34, Mike Puchol via Starlink wrote:
> > Profession Hugh Lewis follows Starlink’s conjuction reports closely, and writes very detailed threads whenever a report comes up:
> >
> > https://twitter.com/ProfHughLewis
> >
> > Latest thread:
> >
> > https://twitter.com/ProfHughLewis/status/1658173801924812803
>
> Unfortunately, Twitter-threads are no longer public.
>
> BR
> Daniel AJ
> _______________________________________________
> Starlink mailing list
> Starlink@lists.bufferbloat.net
> https://lists.bufferbloat.net/listinfo/starlink

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Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months

[tom]

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Great visualization. Dumb question but I can’t figure it out. What are the orange planes labeled “instruments”? They are obviously related o the beams below them but I’m not sure what they are either.

 

Thank you

 

From: Starlink <starlink-bounces@lists.bufferbloat.net> On Behalf Of Mike Puchol via Starlink
Sent: Friday, July 7, 2023 2:35 AM
To: starlink@lists.bufferbloat.net
Subject: Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months

 

Profession Hugh Lewis follows Starlink’s conjuction reports closely, and writes very detailed threads whenever a report comes up:

https://twitter.com/ProfHughLewis

Latest thread:

https://twitter.com/ProfHughLewis/status/1658173801924812803

If you want an idea of -what- they are avoiding, LeoLabs operates a set of radars which track anything larger than 10cm in cross-section, and provides an awesome visualization here:

https://platform.leolabs.space/visualization

(make sure to enable the “debris” checkbox too)

 

Best,

Mike

On Jul 7, 2023 at 08:23 +0200, Daniel AJ Sokolov via Starlink <starlink@lists.bufferbloat.net>, wrote:




On 7/6/23 22:28, blakangel@gmail.com <mailto:blakangel@gmail.com>  wrote:



I think the main point of the article is that the amount of maneuvers
needed is currently increasing exponentially:


Indeed, I read that. But the article does not explain why they think
this trend will continue exponentially.

Obviously it can't continue exponentially forever, because eventually
all satellites are on the move evading one another 100% of the time. :-)

Cheers
Daniel
_______________________________________________
Starlink mailing list
Starlink@lists.bufferbloat.net <mailto:Starlink@lists.bufferbloat.net> 
https://lists.bufferbloat.net/listinfo/starlink


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Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months

[Mike Puchol]

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The instruments are what LeoLabs operates - curtain phased-array radars in various places, which detect and measure objects in orbit as they pass through the curtain’s field - see https://leolabs.space/radars/

They then offer conjuction analysis and warnings to satellite operators under contract, based on their catalog of objects and debris.

Best,

Mike
On Jul 7, 2023 at 14:51 +0200, tom@evslin.com, wrote:
> Great visualization. Dumb question but I can’t figure it out. What are the orange planes labeled “instruments”? They are obviously related o the beams below them but I’m not sure what they are either.
>
> Thank you
>
> From: Starlink <starlink-bounces@lists.bufferbloat.net> On Behalf Of Mike Puchol via Starlink
> Sent: Friday, July 7, 2023 2:35 AM
> To: starlink@lists.bufferbloat.net
> Subject: Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months
>
> Profession Hugh Lewis follows Starlink’s conjuction reports closely, and writes very detailed threads whenever a report comes up:
>
> https://twitter.com/ProfHughLewis
>
> Latest thread:
>
> https://twitter.com/ProfHughLewis/status/1658173801924812803
>
> If you want an idea of -what- they are avoiding, LeoLabs operates a set of radars which track anything larger than 10cm in cross-section, and provides an awesome visualization here:
>
> https://platform.leolabs.space/visualization
>
> (make sure to enable the “debris” checkbox too)
>
> Best,
>
> Mike
> On Jul 7, 2023 at 08:23 +0200, Daniel AJ Sokolov via Starlink <starlink@lists.bufferbloat.net>, wrote:
>
> > quote_type
> >
> > On 7/6/23 22:28, blakangel@gmail.com wrote:
> >
> > > I think the main point of the article is that the amount of maneuvers
> > > needed is currently increasing exponentially:
> >
> > Indeed, I read that. But the article does not explain why they think
> > this trend will continue exponentially.
> >
> > Obviously it can't continue exponentially forever, because eventually
> > all satellites are on the move evading one another 100% of the time. :-)
> >
> > Cheers
> > Daniel
> > _______________________________________________
> > Starlink mailing list
> > Starlink@lists.bufferbloat.net
> > https://lists.bufferbloat.net/listinfo/starlink

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Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months

[Ulrich Speidel]

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Now there is the misuse of the expression "exponentially" in cases when people just mean "a bit faster than before". If you have a time series 1, 2, 4, 6, 8 then you could claim that it's exponential because the first three terms double each time, yet the last four terms could be used to claim that it's linear.

Plus, exponential growth doesn't necessarily mean fast growth. Your 2020 term deposit for 5 years at 1% interest rate with interest reinvested sees your money growing exponentially, too. This is perhaps why decision-makers from the economics sphere tend to get caught out be fast exponential growth (the sort of growth us science and engineering folk tend to think of).

Beyond that: I'm not sure that I can make much of orbital maneuver numbers. Even GEO sats - for which collision probability is very low - undertake regular corrective maneuvers for station-keeping. For anything further down, a maneuver could be a short-term evasive action, a longer term orbit injection or change maneuver, or corrective action to any of these.

Each maneuver uses some of the satellite's propellant reserve. As a general rule, a maneuver executed over a longer period of time is more fuel efficient: A small change in a satellite's trajectory now can lead to a large change down the time axis, with very little propellant use - think Starlink satellites transitioning from launch train to final station over months. Making small corrective adjustments to this over time might bring the total number of maneuvers up, too. Conversely, large short-term corrections dip into fuel reserves, which can impact on service life. So you'd really need to ask which sort of maneuvers these are, and how much each maneuver costs in terms of service life.

--
****************************************************************
Dr. Ulrich Speidel

Department of Computer Science

Room 303S.594
Ph: (+64-9)-373-7599 ext. 85282

The University of Auckland
u.speidel@auckland.ac.nz<mailto:u.speidel@auckland.ac.nz>
http://www.cs.auckland.ac.nz/~ulrich/<http://www.cs.auckland.ac.nz/%7Eulrich/>
****************************************************************
________________________________
From: Starlink <starlink-bounces@lists.bufferbloat.net> on behalf of David Lang via Starlink <starlink@lists.bufferbloat.net>
Sent: Friday, July 7, 2023 6:02 PM
To: blakangel@gmail.com <blakangel@gmail.com>
Cc: starlink@lists.bufferbloat.net <starlink@lists.bufferbloat.net>; Daniel AJ Sokolov <daniel@falco.ca>
Subject: Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months

they have been filling shells (altitude sets), so it makes sense for the numbers
to have been going up.

we'll have to see if they keep going up as much as they move on to different
altitude shells.

David Lang

On Thu, 6 Jul 2023, blakangel@gmail.com wrote:

> I think the main point of the article is that the amount of maneuvers needed
> is currently increasing exponentially: "It's been doubling every six months,
> and the problem with exponential trends is that they get to very large
> numbers very quickly." I'm wondering if they are not taking into account the
> massive amount of satellites that have been launched since the previous six
> month report.
>
> I found the semi-annual reports filed w/ the fcc:
> https://licensing.fcc.gov/myibfs/download.do?attachment_key=23204343<https://licensing.fcc.gov/myibfs/download.do?attachment_key=23204343> and
> https://licensing.fcc.gov/myibfs/download.do?attachment_key=23204338<https://licensing.fcc.gov/myibfs/download.do?attachment_key=23204338> for gen
> 1 and gen 2 constellations.
>
> Still reading them and haven't found the older ones yet to compare.
>
>
> David Lang via Starlink wrote on 7/6/2023 9:49 PM:
>
>> some people are assuming that more satellites launched will mean more
>> maneuvers needed (not recognizing that what matters is only the things at
>> the same altitude)
>>
>> plus, it's a scary large number :-)
>>
>> David Lang
>>
>>  On Thu, 6 Jul 2023, Daniel AJ Sokolov via Starlink wrote:
>>
>>> On 7/6/23 17:54, Dave Taht via Starlink wrote:
>>>>
>>> https://www.space.com/starlink-satellite-conjunction-increase-threatens-space-sustainability<https://www.space.com/starlink-satellite-conjunction-increase-threatens-space-sustainability>
>>>>
>>>> I am under the impression that each sat is capable of about 500 over
>>>> the satellite's lifetime. I am curious as to what they are avoiding.
>>>
>>> Assuming your number of 500 is correct, I don't see any worry here. 12
>>> moves in 6 months makes 492 in 20.5 years. That is less than 500 and
>>> beyond the lifetime expectation of the satellite anyway.
>>>
>>> A I missing something?
>>> Daniel AJ
>>> _______________________________________________
>>> Starlink mailing list
>>> Starlink@lists.bufferbloat.net
>>> https://lists.bufferbloat.net/listinfo/starlink<https://lists.bufferbloat.net/listinfo/starlink>
>>>
>> _______________________________________________
>> Starlink mailing list
>> Starlink@lists.bufferbloat.net
>> https://lists.bufferbloat.net/listinfo/starlink<https://lists.bufferbloat.net/listinfo/starlink>
>
>

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Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months

[Larry Press]

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A little more on LeoLabs:

https://circleid.com/posts/20201108-satellite-and-space-debris-tracking-as-a-service

Larry

________________________________
From: Starlink <starlink-bounces@lists.bufferbloat.net> on behalf of Mike Puchol via Starlink <starlink@lists.bufferbloat.net>
Sent: Friday, July 7, 2023 6:18 AM
To: starlink@lists.bufferbloat.net <starlink@lists.bufferbloat.net>
Subject: Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months

The instruments are what LeoLabs operates - curtain phased-array radars in various places, which detect and measure objects in orbit as they pass through the curtain’s field - see https://leolabs.space/radars/<https://urldefense.com/v3/__https://leolabs.space/radars/__;!!P7nkOOY!q8Arz3UDWiNlKOeNBmYNjSeER74Lye313jqr09DqZhKtMQsgspbU3q6isYZCywvVLpEh6xheI5cDl8v5n_nNa700Fw$>

They then offer conjuction analysis and warnings to satellite operators under contract, based on their catalog of objects and debris.

Best,

Mike
On Jul 7, 2023 at 14:51 +0200, tom@evslin.com, wrote:

Great visualization. Dumb question but I can’t figure it out. What are the orange planes labeled “instruments”? They are obviously related o the beams below them but I’m not sure what they are either.



Thank you



From: Starlink <starlink-bounces@lists.bufferbloat.net> On Behalf Of Mike Puchol via Starlink
Sent: Friday, July 7, 2023 2:35 AM
To: starlink@lists.bufferbloat.net
Subject: Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months



Profession Hugh Lewis follows Starlink’s conjuction reports closely, and writes very detailed threads whenever a report comes up:

https://twitter.com/ProfHughLewis<https://urldefense.com/v3/__https://twitter.com/ProfHughLewis__;!!P7nkOOY!q8Arz3UDWiNlKOeNBmYNjSeER74Lye313jqr09DqZhKtMQsgspbU3q6isYZCywvVLpEh6xheI5cDl8v5n_lMUPtd4A$>

Latest thread:

https://twitter.com/ProfHughLewis/status/1658173801924812803<https://urldefense.com/v3/__https://twitter.com/ProfHughLewis/status/1658173801924812803__;!!P7nkOOY!q8Arz3UDWiNlKOeNBmYNjSeER74Lye313jqr09DqZhKtMQsgspbU3q6isYZCywvVLpEh6xheI5cDl8v5n_m75GwSNw$>

If you want an idea of -what- they are avoiding, LeoLabs operates a set of radars which track anything larger than 10cm in cross-section, and provides an awesome visualization here:

https://platform.leolabs.space/visualization<https://urldefense.com/v3/__https://platform.leolabs.space/visualization__;!!P7nkOOY!q8Arz3UDWiNlKOeNBmYNjSeER74Lye313jqr09DqZhKtMQsgspbU3q6isYZCywvVLpEh6xheI5cDl8v5n_loP4_7LQ$>

(make sure to enable the “debris” checkbox too)



Best,

Mike

On Jul 7, 2023 at 08:23 +0200, Daniel AJ Sokolov via Starlink <starlink@lists.bufferbloat.net<mailto:starlink@lists.bufferbloat.net>>, wrote:


On 7/6/23 22:28, blakangel@gmail.com<mailto:blakangel@gmail.com> wrote:


I think the main point of the article is that the amount of maneuvers
needed is currently increasing exponentially:

Indeed, I read that. But the article does not explain why they think
this trend will continue exponentially.

Obviously it can't continue exponentially forever, because eventually
all satellites are on the move evading one another 100% of the time. :-)

Cheers
Daniel
_______________________________________________
Starlink mailing list
Starlink@lists.bufferbloat.net<mailto:Starlink@lists.bufferbloat.net>
https://lists.bufferbloat.net/listinfo/starlink<https://urldefense.com/v3/__https://lists.bufferbloat.net/listinfo/starlink__;!!P7nkOOY!q8Arz3UDWiNlKOeNBmYNjSeER74Lye313jqr09DqZhKtMQsgspbU3q6isYZCywvVLpEh6xheI5cDl8v5n_n7Ox06Rg$>

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Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months

[Dave Taht]

I think perhaps tracking potential energy transfer from a collision
would be a good baseline?

a BB, moving at 17kph relative to the impact packs quite a wallop. One
at 5kph, far less so. Still, that is much smaller than a centimeter.

A cosmic ray impact on the wrong transistor can be impactful in different ways.

A followon thought is possibly, as satellites are de-orbited would it
be possible to take some debris down with them in some way?

On Fri, Jul 7, 2023 at 4:28 PM Ulrich Speidel via Starlink
<starlink@lists.bufferbloat.net> wrote:
>
> Now there is the misuse of the expression "exponentially" in cases when people just mean "a bit faster than before". If you have a time series 1, 2, 4, 6, 8 then you could claim that it's exponential because the first three terms double each time, yet the last four terms could be used to claim that it's linear.
>
> Plus, exponential growth doesn't necessarily mean fast growth. Your 2020 term deposit for 5 years at 1% interest rate with interest reinvested sees your money growing exponentially, too. This is perhaps why decision-makers from the economics sphere tend to get caught out be fast exponential growth (the sort of growth us science and engineering folk tend to think of).
>
> Beyond that: I'm not sure that I can make much of orbital maneuver numbers. Even GEO sats - for which collision probability is very low - undertake regular corrective maneuvers for station-keeping. For anything further down, a maneuver could be a short-term evasive action, a longer term orbit injection or change maneuver, or corrective action to any of these.
>
> Each maneuver uses some of the satellite's propellant reserve. As a general rule, a maneuver executed over a longer period of time is more fuel efficient: A small change in a satellite's trajectory now can lead to a large change down the time axis, with very little propellant use - think Starlink satellites transitioning from launch train to final station over months. Making small corrective adjustments to this over time might bring the total number of maneuvers up, too. Conversely, large short-term corrections dip into fuel reserves, which can impact on service life. So you'd really need to ask which sort of maneuvers these are, and how much each maneuver costs in terms of service life.
>
> --
> ****************************************************************
> Dr. Ulrich Speidel
>
> Department of Computer Science
>
> Room 303S.594
> Ph: (+64-9)-373-7599 ext. 85282
>
> The University of Auckland
> u.speidel@auckland.ac.nz
> http://www.cs.auckland.ac.nz/~ulrich/
> ****************************************************************
> ________________________________
> From: Starlink <starlink-bounces@lists.bufferbloat.net> on behalf of David Lang via Starlink <starlink@lists.bufferbloat.net>
> Sent: Friday, July 7, 2023 6:02 PM
> To: blakangel@gmail.com <blakangel@gmail.com>
> Cc: starlink@lists.bufferbloat.net <starlink@lists.bufferbloat.net>; Daniel AJ Sokolov <daniel@falco.ca>
> Subject: Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months
>
> they have been filling shells (altitude sets), so it makes sense for the numbers
> to have been going up.
>
> we'll have to see if they keep going up as much as they move on to different
> altitude shells.
>
> David Lang
>
> On Thu, 6 Jul 2023, blakangel@gmail.com wrote:
>
> > I think the main point of the article is that the amount of maneuvers needed
> > is currently increasing exponentially: "It's been doubling every six months,
> > and the problem with exponential trends is that they get to very large
> > numbers very quickly." I'm wondering if they are not taking into account the
> > massive amount of satellites that have been launched since the previous six
> > month report.
> >
> > I found the semi-annual reports filed w/ the fcc:
> > https://licensing.fcc.gov/myibfs/download.do?attachment_key=23204343 and
> > https://licensing.fcc.gov/myibfs/download.do?attachment_key=23204338 for gen
> > 1 and gen 2 constellations.
> >
> > Still reading them and haven't found the older ones yet to compare.
> >
> >
> > David Lang via Starlink wrote on 7/6/2023 9:49 PM:
> >
> >> some people are assuming that more satellites launched will mean more
> >> maneuvers needed (not recognizing that what matters is only the things at
> >> the same altitude)
> >>
> >> plus, it's a scary large number :-)
> >>
> >> David Lang
> >>
> >>  On Thu, 6 Jul 2023, Daniel AJ Sokolov via Starlink wrote:
> >>
> >>> On 7/6/23 17:54, Dave Taht via Starlink wrote:
> >>>>
> >>> https://www.space.com/starlink-satellite-conjunction-increase-threatens-space-sustainability
> >>>>
> >>>> I am under the impression that each sat is capable of about 500 over
> >>>> the satellite's lifetime. I am curious as to what they are avoiding.
> >>>
> >>> Assuming your number of 500 is correct, I don't see any worry here. 12
> >>> moves in 6 months makes 492 in 20.5 years. That is less than 500 and
> >>> beyond the lifetime expectation of the satellite anyway.
> >>>
> >>> A I missing something?
> >>> Daniel AJ
> >>> _______________________________________________
> >>> Starlink mailing list
> >>> Starlink@lists.bufferbloat.net
> >>> https://lists.bufferbloat.net/listinfo/starlink
> >>>
> >> _______________________________________________
> >> Starlink mailing list
> >> Starlink@lists.bufferbloat.net
> >> https://lists.bufferbloat.net/listinfo/starlink
> >
> >
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-- 
Podcast: https://www.linkedin.com/feed/update/urn:li:activity:7058793910227111937/
Dave Täht CSO, LibreQos

Re: [Starlink] orbital maneuvers 12 per sat in the last 6 months

[David Lang]

On Sat, 8 Jul 2023, Dave Taht wrote:

> A followon thought is possibly, as satellites are de-orbited would it
> be possible to take some debris down with them in some way?

not easily, you would have to collide/dock with the debris to change their 
orbit, and that's more likely to break off more parts than to catch things to 
de-orbit.

david Lang