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-   -   Starlink Satellite train (https://www.pprune.org/space-flight-operations/627687-starlink-satellite-train.html)

back to Boeing 2nd Dec 2019 12:35

Starlink Satellite train
 
Plodding across the Atlantic this morning I was absent mindedly staring out the window enjoying the view as slowly but surely my eyes adjusted to the Milky Way coming in to view. A couple of nice shooting starts. And then a satellite passed overhead. And then another. And another and another and another and another. I stopped counting after 20.

After my post flight snooze I googled and found this.

https://en.m.wikipedia.org/wiki/Star...n)?wprov=sfti1

At first I was impressed by what I saw. But after seeing as many as I did I was a little disappointed because it started distracting me from my usual favourites of Orion in all its glory.

60 was distracting enough. Then I read on 12000 of the blighters!!!! I’m all for the advancement of life and knowledge on this blue marble. And the internet is a powerful tool for knowledge. But are we going too far???

wiggy 2nd Dec 2019 14:30


Originally Posted by back to Boeing (Post 10630938)
I’m all for the advancement of life and knowledge on this blue marble. And the internet is a powerful tool for knowledge. But are we going too far???

FWIW these satellites are starting to P off many astronomers, both amateur and professional...

https://www.space.com/spacex-starlin...ervations.html


When the company launched its first set of Starlink internet satellites in May, those with their eyes attuned to the night sky immediately realized that the objects were incredibly bright. Professional astronomers worried the satellites would interfere with scientific observations and amateur appreciation of the stars."That first few nights, it was like, 'Holy not-publishable-word,'" Jonathan McDowell, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics, told Space.com. "That kind of was the wake-up call."

https://www.theverge.com/2019/5/29/1...ight-pollution

https://globalmeteornetwork.org/?author=1

SpringHeeledJack 2nd Dec 2019 15:09

Whilst it's admirable (or malevolent) for the companies to want global internet for all, by further cluttering near-earth space with hundreds and potentially thousands of satellites seems counter-productive to my simple mind. I wonder if the mathematicians can quantify how much higher the chances are of collisions between said satellites and others of the same genre and all the space junk that litters Low Earth Orbit. I realise that Space is big, even that which surrounds us, but adding to the mix just seems like madness to me.

Sallyann1234 2nd Dec 2019 15:19

The crazy thing is that there is no control or oversight over the launch of satellites. It's a purely commercial thing - anyone or any business can send up as many as they can afford. The only regulation is of the frequencies they can use to communicate.

I don't see why they shouldn't be controlled as strictly as airline operations.

clark y 2nd Dec 2019 21:58

Kessler Syndrome?

SpringHeeledJack 3rd Dec 2019 07:13

Very possible. How it hasn't happened in part already is puzzling.

wiggy 3rd Dec 2019 07:30


Originally Posted by Sallyann1234 (Post 10631032)
The crazy thing is that there is no control or oversight over the launch of satellites.

I don't see why they shouldn't be controlled as strictly as airline operations.

I think (from memory, from something I vaguely recall reading) there are agreements about the positioning of geostationary satellites, with them being allocated a "box" to operate in. Other than that - ?

Sallyann1234 3rd Dec 2019 09:05


Originally Posted by wiggy (Post 10631452)
I think (from memory, from something I vaguely recall reading) there are agreements about the positioning of geostationary satellites, with them being allocated a "box" to operate in. Other than that - ?

Geostationary broadcast satellites are positioned according to area coverage and frequency coordination.

wiggy 3rd Dec 2019 09:55


Originally Posted by Sallyann1234 (Post 10631518)
Geostationary broadcast satellites are positioned according to area coverage and frequency coordination.


I'm aware of that, but I also thought (possibly mistakenly) that I had read/heard that because that piece of "real estate" was of such value there was an agreement/coordination system to try and ensure such satellites (and of course it's not just comms sats) remained in an assigned "box" whilst they were operational and that once they became "inop" if possible they were moved out of the geostationary belt.

I'll see if I can find out further...

Edit to add: here you go:

There's a Parking Problem..

Sallyann1234 3rd Dec 2019 10:03


Originally Posted by wiggy (Post 10631573)
I'm aware of that, but I also thought (possibly mistakenly) that I had read/heard that because that piece of "real estate" was of such value there was an agreement/coordination system to try and ensure such satellites (and of course it's not just comms sats) remained in an assigned "box" whilst they were operational and that once they became "inop" if possible they were moved out of the geostationary belt.

I'll see if I can find out further...

​​​​​​Yes, you are right. There is a coordination system for geostationary satellites because there is a limited capacity in the Clarke belt.
But there is no control for all these new satellites that the OP refers to, other than frequency assignments.

wiggy 3rd Dec 2019 10:14


Originally Posted by Sallyann1234 (Post 10631579)
​​​​​​
But there is no control for all these new satellites that the OP refers to, other than frequency assignments.

Correct...I've never claimed otherwise.

Sallyann1234 3rd Dec 2019 10:58


Originally Posted by wiggy (Post 10631589)
Correct...I've never claimed otherwise.

I never said you did :)

John Marsh 4th Dec 2019 19:19

There could be even more:


But SpaceX isn’t alone in its satellite broadband ambitions: An international consortium called OneWeb is aiming to put its own broadband constellation into space with more than a billion dollars in backing from Airbus, SoftBank, Virgin Group and other partners. OneWeb’s first launch is expected to to occur within the next six months.
Geekwire

If thousands of these craft are sent aloft, what's the chance of damage to Moon or Mars mission craft, probe launches, or even future satellite launches?

ORAC 4th Dec 2019 19:26

List of planned constellations at table 1.......

https://www.sciencedirect.com/scienc...6889671930045X

TURIN 5th Dec 2019 19:43

Space is big, really big. I mean you may think its a long way down the road to the chemist but thats just peanuts to space, listen.....


Ah Douglas.

Stribeck 18th Dec 2019 21:39

Apparently SpaceX is considering this issue and are investigating less reflective coatings for the starlink satellites. This will not help with the space debris problem of course, but it makes sense for reducing the effect on astronomy.

Link to news article: spaceflightnow.com/2019/12/09/spacex-to-experiment-with-less-reflective-satellite-coatings-on-next-starlink-launch/

Tankertrashnav 18th Dec 2019 23:37

Turin - thanks - I was trying to remember how that quote went but you saved me the trouble :ok:

RatherBeFlying 19th Dec 2019 02:03

When the Next Asteroid Hits
 
StarLink will have been blocking it from view:(

But when there's money to be made, who cares about shutting down astronomy? Look at all the trouble those pesky scientists have been making over CO²:}

tartare 20th Dec 2019 01:51

The astronomy problem can be solved relatively simply.
Cover `em in Vantablack
Being done already with certain types of less well-publicised satellites... if you catch my drift.

Carry0nLuggage 20th Dec 2019 08:14


Originally Posted by tartare (Post 10643889)
The astronomy problem can be solved relatively simply.
Cover `em in Vantablack
Being done already with certain types of less well-publicised satellites... if you catch my drift.

That will do wonders for the thermal properties of the satellite, especially in LEO. Closing with, and spray painting a rival's satellite with black paint has been proposed as a way of destroying it without filling the orbit with debris. Basically roast it to death.


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