Starlink Thread (split from SpaceX)

[kerbiloid]

Just now, sevenperforce said:

Exactly. They carry onboard fuel to adjust trajectory and stay in space, and enough to perform a rapid deorbit if there was a problem.

So, 12 000 sats raising risk of collision up to percents per year are always in orbit.
If one dies and deorbits, they launch a replacement to keep the cloud same dangerous.

[Technical Ben]

2 minutes ago, kerbiloid said:

This.

And as the 12 000 objects constellation is presumed to be permanently existing, the argument of orbit decay is not applicable.
This cloud of floating contact mines will be existing and make low orbits as dangerous as a minefield.

Just like all those cars, boats and aircraft... oh wait!

[kerbiloid]

1 minute ago, Technical Ben said:

Just like all those cars, boats and aircraft... oh wait!

Cars, boats, and aircrafts can maneuver and stop.

If 12 000 sats start maneuvering in evasive action, the chaos just gets absolutely chaotic.

Edited September 3, 2019 by kerbiloid

[Technical Ben]

Just now, kerbiloid said:

Cars, boats, and aircrafts can maneuver and stop.

And these satellites cannot?

[Rakaydos]

Just now, kerbiloid said:

Cars, boats, and aircrafts can maneuver and stop.

Spacecraft can dodge.

[kerbiloid]

1 minute ago, Technical Ben said:

And these satellites cannot?

1. Are they going to?
2. Will they evade each close satellite?

Yes, they cannot.

[Technical Ben]

Just now, kerbiloid said:

1. Are they going to?
2. Will they evade each close satellite?

Yes, they cannot.

Huh? Can cars evade?

You:

Quote

1. Are they going to?
2. Will they evade each close satellite?

Yes, they cannot.

Me: 

What proof?

[kerbiloid]

2 minutes ago, Rakaydos said:

Spacecraft can dodge.

They can make a torus-like satellite, to let another one pass through the opening.

Just now, Technical Ben said:

Can cars evade?

Can cars move 8 km/s? (Except Tesla).

1 minute ago, Technical Ben said:

Quote

1. Are they going to?
2. Will they evade each close satellite?

Yes, they cannot.

Me: 

What proof?

What proof they are going?

[Technical Ben]

3 minutes ago, kerbiloid said:

They can make a torus-like satellite, to let another one pass through the opening.

Can cars move 8 km/s? (Except Tesla).

What proof they are going?

So. You are saying we need to take every car off the road. Boat out of the sea. And aircraft out the sky... because:

"What proof they are going?" to avoid collisions?

 

Quote

Can cars move 8 km/s? (Except Tesla).

Yes, if you put it in orbit.

Edited September 3, 2019 by Technical Ben

[kerbiloid]

3 minutes ago, Technical Ben said:

So. You are saying we need to take every car off the road. Boat out of the sea. And aircraft out the sky... because:

"What proof they are going?" to avoid collisions?

The false analogies with slow-moving and maneuverable crafts are pointless.

3 minutes ago, tater said:

Some were intended to be deorbited from the start to demonstrate/test that capability.

To be immediately replaced with new ones.
The problem is in the cloud density itself.
It's overdangerous even if use aviation safe distances between trajectories.

Edited September 3, 2019 by kerbiloid

[Technical Ben]

1 minute ago, kerbiloid said:

The false analogies with slow-moving and maneuverable crafts are pointless.

To be immediately replaced with new ones.
The problem is in the cloud density itself.

You are saying the satellites are not maneuverable. Have you played KSP? Is it a false analogy?

Quote

To be immediately replaced with new ones.

Really, did they just launch? I missed that one.

Quote

The problem is in the cloud density itself.

Possibly. But other arguments are nonsensical currently.

[tater]

1 minute ago, kerbiloid said:

The false analogies with slow-moving and maneuverable crafts are pointless.

To be immediately replaced with new ones.
The problem is in the cloud density itself.

It's a LEO constellation.

They cannot have fewer, bigger sats, as the point is to have them above people all the time, and the ground stations as not supposed to be major installations.

Fewer, larger sats with bigger antennas is a 1-way solution, else you need much more powerful ground stations.

[CatastrophicFailure]

13 minutes ago, kerbiloid said:

Cars, boats, and aircrafts can maneuver and stop.

If 12 000 sats start maneuvering in evasive action, the chaos just gets absolutely chaotic.

Just for comparison, on average there are around 12,000 aircraft in the air at any given time*, which are much bigger than Starlinks, in a much smaller “shell” of space. They are highly regulated, and very rarely hit each other at altitude. 

The whole Kessler syndrome thing is way overblown. People forget that space is big. Really, really, big. And the farther out you go the bigger it gets. And most things that aren’t far out don’t stay up forever. 

 

*And as high as 19,000 at once, I recall reading. 

Edited September 3, 2019 by CatastrophicFailure

[kerbiloid]

9 minutes ago, Technical Ben said:

You are saying the satellites are not maneuverable. Have you played KSP? Is it a false analogy?

1. Are you aware that infinite fuel onboard is a cheating? Especially in low orbits.
2. So, one craft passing through the cloud makes a hundred of sats start maneuvering to evade collisions with closest neighbors?

9 minutes ago, Technical Ben said:

Really, did they just launch? I missed that one.

Aren't they going to keep 12 000 in orbit?

9 minutes ago, Technical Ben said:

Possibly. But other arguments are nonsensical currently.

When I hear such "nonsense" arguments, I see that the opponent is out of rational arguments.

8 minutes ago, tater said:

They cannot have fewer, bigger sats, as the point is to have them above people all the time, and the ground stations as not supposed to be major installations.

Fewer, larger sats with bigger antennas is a 1-way solution, else you need much more powerful ground stations.

So, they should consider the grounds stations as a rational alternative.
As well they can't just cover the sky with foil to keep the signal available everywhere. Probably it should be solved by a combination of 1000 km and GSO sats, and the ground signal distribution equipment.
 

7 minutes ago, CatastrophicFailure said:

Just for comparison, on average there are around 12,000 aircraft in the air at any given time*, which are much bigger than Starlinks, in a much smaller “shell” of space. They are highly regulated, and very rarely hit each other at altitude. 

Now have a look at the airlines map and compare it to the straight line of orbit.
You can't command to a sat: "Please, pass from TIKOL to POLIK, then turn to NETAM and follow to RATAM"

7 minutes ago, CatastrophicFailure said:

The whole Kessler syndrome thing is way overblown.

As I've calculated above, the cloud is the Kessler from its appearance. Debris are not required.

Edited September 3, 2019 by kerbiloid

[tater]

4 minutes ago, kerbiloid said:

So, they should consider the grounds stations as a rational alternative.
As well they can't just cover the sky with foil to keep the signal available everywhere. Probably it should be solved by a combination of 1000 km and GSO sats, and the ground signal distribution equipment.
 

GEO is not an option, the goal is low latency. Signal travel time matters.

ESA was complaining... but ESA is funding OneWeb (making their own, competing constellation). This was more about PR than anything else, ESA/OneWeb throwing shade.

[kerbiloid]

3 minutes ago, tater said:

GEO is not an option, the goal is low latency. Signal travel time matters.

ESA was complaining... but ESA is funding OneWeb (making their own, competing constellation). This was more about PR than anything else, ESA/OneWeb throwing shade.

Two mad ideas don't make each other less mad.

Hope, they use opposite inclinations to see the flashdance in the sky more spectacular and to deorbit the scrap faster.

P.S.
Also then I should recalcuate the chances for two madding crowds of sats.

Edited September 3, 2019 by kerbiloid

[mikegarrison]

9 minutes ago, CatastrophicFailure said:

Just for comparison, on average there are around 12,000 aircraft in the air at any given time*, which are much bigger than Starlinks, in a much smaller “shell” of space. They are highly regulated, and very rarely hit each other at altitude. 

They also have active human pilots and automated anti-collision systems and a large network of Air Traffic Control that actively manages the airspace.

[kerbiloid]

And they refuel every landing, unlike the sats.

[Rakaydos]

@Kerbiloid

You seem to be arguing from ignorance, and not accepting "that's not how it works" as an answer.

Very well then.

The surface of the earth is 510 million square Km, which is 510 trillion square meters. even assuming all satelites and debris was at a single altitude, properly coordinated, that's room for easily billions of hundred meter sats to never collide. And not all sats are at the same altitude, so you have larger and larger shells where sats can be, each able to contain more and more sats without interfering.

That's assuming all orbits are properly planned. what about when they arnt? Sats can dodge, we tell you. How can you be sure, you ask, because the ESA just did it. 

There's international rules about uncontrolled debris, and a dedicated "graveyard orbit" for Geosynchronus Orbit sats to retire to, when they don't have enough fuel to reenter earth.

 

These things have been thought of. Chill.

[CatastrophicFailure]

10 minutes ago, mikegarrison said:

They also have active human pilots and automated anti-collision systems and a large network of Air Traffic Control that actively manages the airspace.

And Starlink will have its own automatic anti-collision system, as well as ground monitoring by multiple systems. 

8 minutes ago, kerbiloid said:

And they refuel every landing, unlike the sats.

How is that even relevant? A sat that’s low on fuel will be safely deorbited and no longer a concern. 

 

Also:

Yeah, this whole non-issue is just ESA grandstanding for their own product. 

[mikegarrison]

13 minutes ago, tater said:

This was more about PR than anything else, ESA/OneWeb throwing shade.

Yes, it kind of seemed like that. But it does make me wonder why the FCC (or whoever does the same thing in Europe) is essentially allowed to allocate orbital space that kind of belongs to all countries.

3 minutes ago, Rakaydos said:

@Kerbiloid

You seem to be arguing from ignorance, and not accepting "that's not how it works" as an answer.

Very well then.

The surface of the earth is 510 million square Km, which is 510 trillion square meters. even assuming all satelites and debris was at a single altitude, properly coordinated, that's room for easily billions of hundred meter sats to never collide. And not all sats are at the same altitude, so you have larger and larger shells where sats can be, each able to contain more and more sats without interfering.

That's assuming all orbits are properly planned. what about when they arnt? Sats can dodge, we tell you. How can you be sure, you ask, because the ESA just did it. 

There's international rules about uncontrolled debris, and a dedicated "graveyard orbit" for Geosynchronus Orbit sats to retire to, when they don't have enough fuel to reenter earth.

 

These things have been thought of. Chill.

And yet ... https://en.wikipedia.org/wiki/2009_satellite_collision

[kerbiloid]

1 minute ago, CatastrophicFailure said:

10 minutes ago, kerbiloid said:

And they refuel every landing, unlike the sats.

How is that even relevant? A sat that’s low on fuel will be safely deorbited and no longer a concern. 

Every month? I guessed, sats live for a decade or so, so they need fuel.

4 minutes ago, Rakaydos said:

The surface of the earth is 510 million square Km, which is 510 trillion square meters. even assuming all satelites and debris was at a single altitude, properly coordinated, that's room for easily billions of hundred meter sats to never collide. And not all sats are at the same altitude, so you have larger and larger shells where sats can be, each able to contain more and more sats without interfering.

Please, find the error in my calculations. I believe, it exists.

[Rakaydos]

2 minutes ago, kerbiloid said:

Every month? I guessed, sats live for a decade or so, so they need fuel.

Please, find the error in my calculations. I believe, it exists.

...how much fuel do you think a sat needs to dodge a 5m target, even just a quarter orbit out?

And can you repost your "calculations"? I must have missed them the first time through.

[kerbiloid]

2 minutes ago, Rakaydos said:

...how much fuel do you think a sat needs to dodge a 5m target, even just a quarter orbit out?

And return back. And do this every time when another one of ~20 000 (thanks, ESA!) is passing by.
And every time when one changes its orbit, a hundred of others oin intersecting orbits should react to evade him in turn.

4 minutes ago, Rakaydos said:

And can you repost your "calculations"?

 

[Rakaydos]

You could really use better labels, but it appears you assume every satellite must have it's own "orbital torus", and if any overlap ever it's Kessler time.

In fact, every geosynchronus satellite ever has shared the same "orbital torus" without harmfull effect. Starlink intends to have 66 sats in each plane each sharing an orbital torus with the rest of that plane, for each plane in each inclination.