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Old 18th June 2019, 03:02 AM   #1
The Great Zaganza
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We need to talk about Starlink

So Musk send the first 60 Starlink satellites into orbit -
the first 60 of a planned total of 12,000 by the mid 2020s.

The goal is a global, everywhere accessible and faster internet.

this is a nice background on the technological and economic aspects of it:

https://www.youtube.com/watch?v=giQ8xEWjnBs


Currently, I am thinking more of the possible political implications, and what they will mean for the project.

Starlink could make attempts of governments to control the internet access of their citizens pointless.
Since information control is a critical part of how China and other regimes keep control, I doubt that they will let Musk just take away their monopoly on what is acceptable online and what is not.

I fear that SpaceX is going to be the trigger for a Space War.
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Old 18th June 2019, 05:02 AM   #2
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Or maybe their control is being eroded now, and the last step will be accepted as inevitable.

hmm, are they merely cell towers in space? Cell phones will suffice? Or is special hardware needed for the consumer? Hardware is easier to control?
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Old 18th June 2019, 05:43 AM   #3
The Great Zaganza
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Originally Posted by casebro View Post
Or maybe their control is being eroded now, and the last step will be accepted as inevitable.

hmm, are they merely cell towers in space? Cell phones will suffice? Or is special hardware needed for the consumer? Hardware is easier to control?
you'll need a pizza-box sized antenna.
So yeah, China might demand that all units sold domestically have a build-in Great Firewall.
Doesn't mean that local will only use those< and China would have no way to check traffic.
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Old 18th June 2019, 11:11 AM   #4
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I think that it will be interesting as we get wave after wave of these new micro satellites, not just Star Link. What will the risks be after we say have a million of them up there, will it make launching more of a challenge?
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Old 18th June 2019, 11:44 AM   #5
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I know there's some concern for astronomers. 12,000 new satellites might wreak havoc with time-exposed pictures.

But I'm not sure they would be all that intrusive. Given the size of the orbiter, its orbit height, and the general distribution (assuming it is even), how many could be seen at any one time? It seems like an interesting math problem but I don't know how to compute the cone of visibility for a single satellite.
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Old 18th June 2019, 12:08 PM   #6
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Originally Posted by The Great Zaganza View Post
you'll need a pizza-box sized antenna.
I guess that the Starlink (etc) folk have totally open specs on what's broadcast (comms protocols, frequencies, etc). If so, then the market for receivers should be very open. I wonder if there are estimates of likely retail prices?

Quote:
So yeah, China might demand that all units sold domestically have a build-in Great Firewall.
Doesn't mean that local will only use those< and China would have no way to check traffic.
I wonder if a built-in Great Firewall is even possible. Seems to me it would require quite a lot of memory and some serious CPU ... the actual GF is huge server farms
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Old 18th June 2019, 12:11 PM   #7
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current estimate for first generation Starlink antenna/router is $200.
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Old 18th June 2019, 02:43 PM   #8
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Originally Posted by alfaniner View Post
I know there's some concern for astronomers. 12,000 new satellites might wreak havoc with time-exposed pictures.

But I'm not sure they would be all that intrusive. Given the size of the orbiter, its orbit height, and the general distribution (assuming it is even), how many could be seen at any one time? It seems like an interesting math problem but I don't know how to compute the cone of visibility for a single satellite.
There's been a lot of FUD and outright nuttery about this, the worst claiming that it'd cause light pollution that would ruin stargazing and describing their horror at seeing a few points of light in the sky and fury that SpaceX would dare do this without consulting anyone (despite the plans having been quite open, and SpaceX actually working with astronomers to minimize interference).

The reality is pretty much as you described: only a handful of Starlink satellites will be high in the sky at any given time, and they will become less visible as they gain altitude and orient with their solar panels "behind" them as seen from Earth. The satellites from the first launch are already much more difficult to observe. They will be an minor issue for a small percentage of long-term exposures.
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Old 18th June 2019, 02:57 PM   #9
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Originally Posted by JeanTate View Post
I guess that the Starlink (etc) folk have totally open specs on what's broadcast (comms protocols, frequencies, etc). If so, then the market for receivers should be very open. I wonder if there are estimates of likely retail prices?
The pizza box is a two-way phased array that electronically switches from satellite to satellite in a constellation of thousands as they move overhead, requiring intimate knowledge of their orbits and inter-satellite routing. There aren't standards for this sort of thing.


Originally Posted by JeanTate View Post
I wonder if a built-in Great Firewall is even possible. Seems to me it would require quite a lot of memory and some serious CPU ... the actual GF is huge server farms
All you'd have to do is route traffic from Chinese terminals through the those server farms. The main problem for Starlink would be the concentration of traffic from across China through those satellites with ground links to the Great Firewall servers. And latency would suffer, of course.
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Old 18th June 2019, 02:58 PM   #10
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Originally Posted by cjameshuff View Post
...

The reality is pretty much as you described: only a handful of Starlink satellites will be high in the sky at any given time, and they will become less visible as they gain altitude and orient with their solar panels "behind" them as seen from Earth. The satellites from the first launch are already much more difficult to observe. They will be an minor issue for a small percentage of long-term exposures.
Isn't the degrees apart mentioned in the OP link ? Or somewhere... Altitude, sphere diameter, sphere area, divide by 12,000= area per sat, trig degrees apart?

Whatever, time to sell your ATT and Sprint stock?
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Old 18th June 2019, 05:04 PM   #11
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Thanks. I think I have some significant misunderstandings on this.

Originally Posted by cjameshuff View Post
The pizza box is a two-way phased array that electronically switches from satellite to satellite in a constellation of thousands as they move overhead, requiring intimate knowledge of their orbits and inter-satellite routing. There aren't standards for this sort of thing.
If the receiver includes GPS, the (very!) local position and time are a piece of cake.

Satellite orbits are ďjustĒ some spherical geometry and Keplerís third (or equivalent); initial values are a big problem of course.

Very little memory or CPU needed for any of that.

What am I missing?

Quote:
All you'd have to do is route traffic from Chinese terminals through the those server farms. The main problem for Starlink would be the concentration of traffic from across China through those satellites with ground links to the Great Firewall servers. And latency would suffer, of course.
Right.

As I understand it, thereís no need for any particular terrestrial component ... your receiver can connect - via a network - to the internet via any of many ground stations, not just GF ones (in China or elsewhere).
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Old 18th June 2019, 05:07 PM   #12
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Originally Posted by The Great Zaganza View Post
current estimate for first generation Starlink antenna/router is $200.
Cheaper than many/most smartphones, but quite a hefty price for some ~billions of those currently without reliable, even modest speed internet access.
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Old 18th June 2019, 06:12 PM   #13
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Originally Posted by JeanTate View Post
If the receiver includes GPS, the (very!) local position and time are a piece of cake.

Satellite orbits are ďjustĒ some spherical geometry and Keplerís third (or equivalent); initial values are a big problem of course.

Very little memory or CPU needed for any of that.

What am I missing?
It's not a matter of CPU or memory usage. The terminals have to be tied into the system to get constant updates on the satellite locations, have to route across the constellation to another downlink (in the initial version, just a hop off the satellite, but with optical inter-satellite links in the later versions), switch that routing around as the network geometry changes including changes in surface to orbit hops at both ends, etc. And you also need a phased array transceiver that can switch almost instantly between satellites and likely handle signals from multiple satellites simultaneously, something that is going to require quite a bit of specialized, high-performance, and very application-specific signal processing.

There are no standards for any of this because nobody's ever done this before. There's a substantial amount of new engineering involved.


Originally Posted by JeanTate View Post
As I understand it, thereís no need for any particular terrestrial component ... your receiver can connect - via a network - to the internet via any of many ground stations, not just GF ones (in China or elsewhere).
There's no technological reason you couldn't connect from a terminal in China to any other location. That doesn't mean the software has to permit it. The routes taken by traffic from a US-licensed terminal in a US embassy and a Chinese-licensed terminal in a coffee shop across the street might be completely different.
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Old 19th June 2019, 06:23 AM   #14
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Originally Posted by alfaniner View Post
I know there's some concern for astronomers. 12,000 new satellites might wreak havoc with time-exposed pictures.

But I'm not sure they would be all that intrusive. Given the size of the orbiter, its orbit height, and the general distribution (assuming it is even), how many could be seen at any one time? It seems like an interesting math problem but I don't know how to compute the cone of visibility for a single satellite.

I think it will spell the end of earth based astronomy.

https://www.theverge.com/2019/5/25/1...ek-netherlands

This is 60 of them. 12,000 will light up the night sky to the point where constellations will be unrecognisable.


Still, progress, eh?
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Old 19th June 2019, 09:18 AM   #15
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Originally Posted by cjameshuff View Post
There's been a lot of FUD and outright nuttery about this, the worst claiming that it'd cause light pollution that would ruin stargazing
That is funny!
part of star gazing is catching sight of satellites, much better than all the airplanes
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Old 19th June 2019, 09:24 AM   #16
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Originally Posted by 3point14 View Post
I think it will spell the end of earth based astronomy.

https://www.theverge.com/2019/5/25/1...ek-netherlands

This is 60 of them. 12,000 will light up the night sky to the point where constellations will be unrecognisable.


Still, progress, eh?
I am not so sure about that:
https://www.skyandtelescope.com/obse...nk-satellites/

They seem to say they are often dim and right at the edge of eyeball visibility
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Old 19th June 2019, 09:31 AM   #17
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There is a risk to astronomy due to Starlink, because they fly so low.
But since their movement is so predictable, it should be possible to compensate.
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Old 19th June 2019, 09:36 AM   #18
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Originally Posted by Dancing David View Post
I am not so sure about that:
https://www.skyandtelescope.com/obse...nk-satellites/

They seem to say they are often dim and right at the edge of eyeball visibility
I wouldn't claim to be an expert and I hope you're right, I just suspect yhat there will be unexpected consequences for amateur astronomers.



Originally Posted by The Great Zaganza View Post
There is a risk to astronomy due to Starlink, because they fly so low.
But since their movement is so predictable, it should be possible to compensate.

Which is fine if you have the tech to do that sort of thing. If you're just using a home telescope to interest your child in astronomy for the first time, I imagine it's going to be utterly infuriating to have these things crossing your view at amazingly regular intervals.
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Old 19th June 2019, 09:45 AM   #19
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Originally Posted by 3point14 View Post
I wouldn't claim to be an expert and I hope you're right, I just suspect yhat there will be unexpected consequences for amateur astronomers.






Which is fine if you have the tech to do that sort of thing. If you're just using a home telescope to interest your child in astronomy for the first time, I imagine it's going to be utterly infuriating to have these things crossing your view at amazingly regular intervals.
I'm trying to some maths... so earth is made up of around 200 million square miles, since these will be at some altitude (though there are 3 layers so calculating it is tough), there is actually more square miles of area up there. But even just taken at the ground, that is one satellite per 16,000 square miles. A decent amateur telescope is showing 1 square arc second. There are 648,000^2 square arc seconds of sky. So the odds of a skylink sat being in your field of vision at any given time is... so minimal I'm afraid to even calculate it. Someone correct my math?
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Old 19th June 2019, 09:51 AM   #20
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Originally Posted by lobosrul5 View Post
I'm trying to some maths... so earth is made up of around 200 million square miles, since these will be at some altitude (though there are 3 layers so calculating it is tough), there is actually more square miles of area up there. But even just taken at the ground, that is one satellite per 16,000 square miles. A decent amateur telescope is showing 1 square arc second. There are 648,000^2 square arc seconds of sky. So the odds of a skylink sat being in your field of vision at any given time is... so minimal I'm afraid to even calculate it. Someone correct my math?

That's reassuring. I am probably unreasonably suspicious of this in terms of impact on the night sky. (In terms of communications technology, this is very impressive and should last the rest of human history (about 75 odd years)
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Old 19th June 2019, 10:41 AM   #21
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Thanks.
Originally Posted by cjameshuff View Post
It's not a matter of CPU or memory usage. The terminals have to be tied into the system to get constant updates on the satellite locations, have to route across the constellation to another downlink (in the initial version, just a hop off the satellite, but with optical inter-satellite links in the later versions), switch that routing around as the network geometry changes including changes in surface to orbit hops at both ends, etc. And you also need a phased array transceiver that can switch almost instantly between satellites and likely handle signals from multiple satellites simultaneously, something that is going to require quite a bit of specialized, high-performance, and very application-specific signal processing.

There are no standards for any of this because nobody's ever done this before. There's a substantial amount of new engineering involved.
That's part of what I was missing.

However, it is surely in Starlink's interests to make the protocols etc as open and standardized as possible, isn't it? Doing so would give them first mover advantage (and making it more difficult for a competitor to introduce a quite different standard), as well as encouraging the manufacture of pizza boxes.

Quote:
There's no technological reason you couldn't connect from a terminal in China to any other location. That doesn't mean the software has to permit it. The routes taken by traffic from a US-licensed terminal in a US embassy and a Chinese-licensed terminal in a coffee shop across the street might be completely different.
Right.

And having terminals not licensed by China, in China, could be made some kind of punishable offense. Like what was (once?) tried with satellite dishes.

I wonder what %-age of the world market for Starlink terminals Chinese manufacturers will end up with?

Unrelated question: how do you connect your fave internet device - tablet, smartphone, PC, ... - to the terminal? Ethernet cable? Bluetooth? And presumably you'd encourage up to a household's worth of such connections, or maybe even a small apartment building's worth (ground floor residents may find it challenging to "see the sky").
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Old 19th June 2019, 10:52 AM   #22
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Originally Posted by The Great Zaganza View Post
There is a risk to astronomy due to Starlink, because they fly so low.
But since their movement is so predictable, it should be possible to compensate.
Maybe, but I doubt that it would be easy.

And some astronomy facilities will be hit far harder than others.

Any Starlink satellite - in sunlight! - will be screamingly obvious to any contemporary optical survey, should it cross the field being observed ... after all, geosats are very easily spotted by even SDSS, much less the Subaru HSC or the future LSST.

I suspect the hardest hit will be the LSST, closely followed by the large field supernova hunters.

Trivia: when PanSTARRs was being designed, the US DOD was very concerned that it would "spot" all manner of secret missions, and may have succeeded in getting the consortium to somehow censor their data (if in sunlight and in the field being imaged, all satellites bigger than a metre (from memory) would leave a very clear trail). I think they learned to stop worrying, not least because the Russian and Chinese (say) military were more than capable of finding and imaging the DOD satellites on their own.
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Old 19th June 2019, 11:11 AM   #23
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Aside from the initial cost of the antenna what is the monthly/daily data usage fee going to be? I really don't think it will alter coverage in most of the populated areas, but will be usable in areas that have sparse cell towers currently.
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Old 19th June 2019, 12:44 PM   #24
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Originally Posted by 3point14 View Post
I think it will spell the end of earth based astronomy.

https://www.theverge.com/2019/5/25/1...ek-netherlands

This is 60 of them. 12,000 will light up the night sky to the point where constellations will be unrecognisable.


Still, progress, eh?
Absolute nonsense. 12000 satellites, spread around the entire earth, will mean an average of one for every 16400 square miles of earth's surface. There will never be anything like that "train" of 60 except right after they launch. In operation they will be higher altitude and a different orientation and you will have a hard time even seeing one of them.
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Old 19th June 2019, 12:48 PM   #25
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Originally Posted by phunk View Post
<snip> In operation they will be higher altitude and a different orientation and you will have a hard time even seeing one of them.
Unless your telescope has a diameter of 8m (or even 2m), and your detectors are state-of-the-art CCDs.

OTOH, if your telescope is in Antarctica ...
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Old 19th June 2019, 02:22 PM   #26
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Originally Posted by 3point14 View Post
I think it will spell the end of earth based astronomy.

https://www.theverge.com/2019/5/25/1...ek-netherlands

This is 60 of them. 12,000 will light up the night sky to the point where constellations will be unrecognisable.


Still, progress, eh?
...and there's the nuttery. Why let physical plausibility get in the way of some good sensationalist FUD?
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Old 19th June 2019, 02:24 PM   #27
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Originally Posted by Dancing David View Post
I am not so sure about that:
https://www.skyandtelescope.com/obse...nk-satellites/

They seem to say they are often dim and right at the edge of eyeball visibility
Association of Universities for Research in Astronomy on the topic:
https://www.aura-astronomy.org/news/...of-satellites/

"In the case of the full constellation of Starlink satellites, initial calculations show that LSST images would, on average, contain about one satellite trail per visit for an hour or two after sunset and before sunrise. A very conservative upper limit on the number of LSST pixels affected by Starlink satellites is about 0.01%, and quite likely smaller. Therefore, for LSST, even a constellation of about 10,000 Starlink satellites would be a nuisance rather than a real problem."
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Old 19th June 2019, 03:01 PM   #28
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Originally Posted by lobosrul5 View Post
I'm trying to some maths... so earth is made up of around 200 million square miles, since these will be at some altitude (though there are 3 layers so calculating it is tough), there is actually more square miles of area up there. But even just taken at the ground, that is one satellite per 16,000 square miles. A decent amateur telescope is showing 1 square arc second. There are 648,000^2 square arc seconds of sky. So the odds of a skylink sat being in your field of vision at any given time is... so minimal I'm afraid to even calculate it. Someone correct my math?
The first phase has 24 equally spaced planes at 550 km altitude with 53 degrees inclination, containing 66 satellites each...5.45 degrees apart within each plane. Each will be 660 km from the preceding and next satellite in its plane, so two satellites will be about 60 degrees apart seen from the ground when their midpoint passes overhead...120 lunar diameters.

There will be several of those planes crossing the sky at higher latitudes, but that's still several orders of magnitude short of the more ridiculous claims. And just think about it: why do they need so many satellites to provide internet access? Because in LEO, for any given location on Earth's surface, most of them are going to be below the horizon! There's a weird sort of pseudo flat-eartherism in the more overwrought complaints, as if there's only one sky and everything in it will be visible everywhere.

Additionally, in the summer, near the poles, they will be in sunlight most or all of the night, but the rest of the year they will be in Earth's shadow except near sunrise and sunset, and quite invisible.
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Old 19th June 2019, 03:29 PM   #29
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Originally Posted by cjameshuff View Post
...and there's the nuttery.
Oh, relax. I'm still gathering data.
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Old 20th June 2019, 04:52 AM   #30
cjameshuff
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Originally Posted by 3point14 View Post
Oh, relax. I'm still gathering data.
Perhaps...just a thought...do so before making absurd claims?

Not that it actually takes any additional data, a few seconds of thought suffices to show that your claim that "12,000 will light up the night sky to the point where constellations will be unrecognisable" is physically impossible.
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Old 20th June 2019, 05:47 AM   #31
The Great Zaganza
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Originally Posted by bknight View Post
Aside from the initial cost of the antenna what is the monthly/daily data usage fee going to be? I really don't think it will alter coverage in most of the populated areas, but will be usable in areas that have sparse cell towers currently.
For the base rate, probably quite low - and remember that multiple people can use it at the same time.
SpaceX will most likely run a Premium system for users requiring maximum speed, such as HFT trading software, and make them pay for it.
If you are willing to accept slower rates you will pay a lot less.
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Old 20th June 2019, 05:56 AM   #32
3point14
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Originally Posted by cjameshuff View Post
Perhaps...just a thought...do so before making absurd claims?
Good god no. Why would I do that. I actually wanted an answer and, on the internet, the best way to do that is to do what I did.

Thank you for your input.


Quote:
Not that it actually takes any additional data, a few seconds of thought suffices to show that your claim that "12,000 will light up the night sky to the point where constellations will be unrecognisable" is physically impossible.
Now I know that. Then I didn't. Seems to be working quite well so far.
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Old 20th June 2019, 05:59 AM   #33
bknight
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Originally Posted by The Great Zaganza View Post
For the base rate, probably quite low - and remember that multiple people can use it at the same time.
SpaceX will most likely run a Premium system for users requiring maximum speed, such as HFT trading software, and make them pay for it.
If you are willing to accept slower rates you will pay a lot less.
In other words, they haven't announced a pricing structure. I agree it will be less if slower speeds are acceptable. But this is really structured for those that don't have for those wo don't have any coverage currently.
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Old 20th June 2019, 08:01 AM   #34
Darat
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Originally Posted by 3point14 View Post
Good god no. Why would I do that. I actually wanted an answer and, on the internet, the best way to do that is to do what I did.



Thank you for your input.









Now I know that. Then I didn't. Seems to be working quite well so far.
How dare you ask about something you don't know!
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Old 20th June 2019, 08:06 AM   #35
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Originally Posted by Darat View Post
How dare you ask about something you don't know!
Oh, he had a point. I did loudly proclaim 'facts' from a position of no knowledge.
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Old 21st June 2019, 01:16 AM   #36
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Originally Posted by Dancing David View Post
I am not so sure about that:
https://www.skyandtelescope.com/obse...nk-satellites/

They seem to say they are often dim and right at the edge of eyeball visibility
I read that article. It doesn't seem to say that at all. Here's what it says on the issue:

Quote:
A Million Points of Unwanted Light?
Although the sight of five dozen satellites in a row will take your breath away, not a few of us are concerned about the volume of traffic over our heads. Yes, there's a lot of space up there. We get it. But in 9 years, when 12,000 of them will be crawling the skies like so many ants, will it detract from the sight of the stars at night? Some will say that most of the units will be too high to see with the naked eye, and my May 28th observation seems to be proving the point, but that lowest and most populated belt ó the 7,500 at 340 kilometers altitude ó will almost certainly be visible. Not just in bright twilight either. My May 25th sighting was made at 11:25 p.m.

If you're an astrophotographer, trails from Starlink may be unavoidable and require frequent and deft use of your photo program's cloning tool. For professional astronomers, imaging headaches undoubtedly lie ahead. For the visual observer, will it mean a constant reminder of machines on parade while seeking the solace of a dark sky?

In response to online concerns from amateur and professional astronomers, planetary astronomer Alex Parker tweeted his concerns that "If SpaceX launches all 12,000, they will outnumber stars visible to the naked eye," and estimates that "at midsummer midnight in Seattle about 500 of them will both be above the horizon and directly illuminated by the Sun."
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Old 21st June 2019, 10:06 PM   #37
Roboramma
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Originally Posted by cjameshuff View Post
Perhaps...just a thought...do so before making absurd claims?

Not that it actually takes any additional data, a few seconds of thought suffices to show that your claim that "12,000 will light up the night sky to the point where constellations will be unrecognisable" is physically impossible.
I think "constellations will be unrecognisable" was hyperbole.

Having some concern about the implications for stargazers of having 12,000 new satellites, at least 7,500 of which, according to the article I quoted, will be visible to the naked eye.
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Old 21st June 2019, 10:22 PM   #38
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The reason why SpaceX was granted permission to put so many satellites into orbit at all was that they are capable to decelerate on their own to burn up in the atmosphere with very little debris left.
Given the pace of technology, current tech Starlink satellites have probably less than 20 years of operational life anyway.
So the problem is temporary.
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Old 21st June 2019, 10:30 PM   #39
Roboramma
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Originally Posted by The Great Zaganza View Post
The reason why SpaceX was granted permission to put so many satellites into orbit at all was that they are capable to decelerate on their own to burn up in the atmosphere with very little debris left.
Given the pace of technology, current tech Starlink satellites have probably less than 20 years of operational life anyway.
So the problem is temporary.
Just two comments. First, I'm actually very excited about this. I think it's a great thing. I just think we shouldn't dismiss concerns out of hand when there do seem to be some legitimate issues.

Second, regarding your comment, I understand that the specific satellites being put up now will have a limited life and can be deorbited without problem. But I also doubt that once Starlink is up and running they'll stop the project entirely. Old satellites will be replaced with new ones. Maybe those new ones will be placed in a higher orbit if concerns with being too visible become an issue, and maybe something else will be done (they are already talking about making them less reflective). On the other hand, once the thing is up and running we may simply end up with a new normal that is unlikely to be changed. If starlink becomes a popular choice as an internet provider, people are unlikely to give that up because a few stargazers are unhappy with it.

So I don't think the issue is as temporary as you suggest.
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Old 21st June 2019, 10:41 PM   #40
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Sure, if the concept works, it will become a fixture - but as you said, future versions might be designed to minimize the visual impact.
What won't happen is that the satellites will be move to a higher orbit - the opposite is more likely: sending the signal up and down is the most significant delay in the system, and the clear goal is to be faster than terrestrial solutions.

And yes, I do think that as space launches get cheaper, a number of artificial "shells" of stations and satellites is inevitable, and if nothing else, Musk is wise to get squatter's rights in this orbit before others are ready.
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