SpaceX F9: Starlink v1 Flight 1 : November 11, 2019 - DISCUSSION

[Joffan]

We had a glimpse of a tension rod just at the end there.

[Paul_G]

Here's that reused fairing heading for an ocean recovery.

Didn't they say they were not recovering the fairings due to weather conditions?

I believe the Fairing Capture ships reported issues with their nets due to rough seas enroute, and returned to a port for repairs. The 'fish it out of the water' process will be attempted instead.

[Nomadd]

Would be cool if SpaceX would be able to turn around and continue to use 1048.x for Starlink flights. Would be a great way to verify the amount of times F9 can be reused, as well as give customer confidence for highly reused boosters.

Deploying the initial 1440 sat constellation with the same rocket would be impressive. Only 22 flights to go.

[sevenperforce]

We had a glimpse of a tension rod just at the end there.

So are all of the sats somehow pressure-clamped onto it from the end, and then it gets dropped and they all float off?

[marsbase]

Unlike the previous Starlink satellite release, this second stage was not spinning to impart a differential momentum to the satellites, thus causing them to slowly separate from each other.  There must be some other mechanism to separate the satellites from each other this time.

[sevenperforce]

Unlike the previous Starlink satellite release, this second stage was not spinning to impart a differential momentum to the satellites, thus causing them to slowly separate from each other.  There must be some other mechanism to separate the satellites from each other this time.

The webcast said they just sorta bump into each other and drift apart that way.

[marsbase]

Unlike the previous Starlink satellite release, this second stage was not spinning to impart a differential momentum to the satellites, thus causing them to slowly separate from each other.  There must be some other mechanism to separate the satellites from each other this time.

The webcast said they just sorta bump into each other and drift apart that way.

I didn't hear that and it seems unlikely.  The webcast did mention(at 1:00:17) that they were designed so they would not be damaged if they bumped into each other.  Didn't say this was a disbursement mechanism.

[Captain Crutch]

I'm sure releasing the tension bars causes a spring like motion which then propells and spreads the sats away from the stage and eachother. Just a guess but it seems pretty logical, things under tension just tend to spring back once thetension is released.

[spacenut]

Did the Octograbber get the booster? 

[marsbase]

I'm sure releasing the tension bars causes a spring like motion which then propells and spreads the sats away from the stage and eachother. Just a guess but it seems pretty logical, things under tension just tend to spring back once thetension is released.

You may be right, but that's not what SpaceX thought on the previous launch.  They were very deliberate in spinning the second stage and explained that this would provide the necessary differential momentum.  Maybe there are small springs between the satellites that are released at the time the tension bar is released.  Something is different this time.

[mainmind]

It was said up-thread that this batch of satellites do not have the inter-satellite laser links. Does anyone know when that will be added? It seemed like the whole "link" part of Starlink and an important component for faster global communications.
Thanks

[docmordrid]

It was said up-thread that this batch of satellites do not have the inter-satellite laser links. Does anyone know when that will be added? It seemed like the whole "link" part of Starlink and an important component for faster global communications.
Thanks

Gwynne Shotwell at IAC2019,

CNN...

>
The 60 satellites that we already flew are capable of operations, but the next version will have upgraded technology. By late next year, we'll be flying satellite with lasers that allow them to talk to each other in space and share data, which ensures customers will never lose service.
>

>

[eriblo]

I'm sure releasing the tension bars causes a spring like motion which then propells and spreads the sats away from the stage and eachother. Just a guess but it seems pretty logical, things under tension just tend to spring back once thetension is released.

You may be right, but that's not what SpaceX thought on the previous launch.  They were very deliberate in spinning the second stage and explained that this would provide the necessary differential momentum.  Maybe there are small springs between the satellites that are released at the time the tension bar is released.  Something is different this time.

The second stage was clearly rotating at separation for this launch as well.

[rklaehn]

Does anybody have preliminary two line elements for this batch of satellites, or a link to a ground track display? I would love to see them this time.

[mainmind]

It was said up-thread that this batch of satellites do not have the inter-satellite laser links. Does anyone know when that will be added? It seemed like the whole "link" part of Starlink and an important component for faster global communications.
Thanks

Gwynne Shotwell at IAC2019,

CNN...

>
The 60 satellites that we already flew are capable of operations, but the next version will have upgraded technology. By late next year, we'll be flying satellite with lasers that allow them to talk to each other in space and share data, which ensures customers will never lose service.
>

>

Thanks

So the network topology they're going for with the current iteration is akin to bent-pipe reflectors taking between users and ground stations? And that's the version that's going to go live for northern US and parts of Canada next year? How many ground stations do they have set up now?

[rsdavis9]

Does anybody have preliminary two line elements for this batch of satellites, or a link to a ground track display? I would love to see them this time.

https://www.heavens-above.com/PassSummary.aspx?satid=70003

[marsbase]

I'm sure releasing the tension bars causes a spring like motion which then propells and spreads the sats away from the stage and eachother. Just a guess but it seems pretty logical, things under tension just tend to spring back once thetension is released.

You may be right, but that's not what SpaceX thought on the previous launch.  They were very deliberate in spinning the second stage and explained that this would provide the necessary differential momentum.  Maybe there are small springs between the satellites that are released at the time the tension bar is released.  Something is different this time.

The second stage was clearly rotating at separation for this launch as well.

Aha!  You are right.  It's not rotating as rapidly as last time, but there is a spin there.  Also not much background to view it against.  Ok, I retract my observation.

[John Santos]

I'm sure releasing the tension bars causes a spring like motion which then propells and spreads the sats away from the stage and eachother. Just a guess but it seems pretty logical, things under tension just tend to spring back once thetension is released.

You may be right, but that's not what SpaceX thought on the previous launch.  They were very deliberate in spinning the second stage and explained that this would provide the necessary differential momentum.  Maybe there are small springs between the satellites that are released at the time the tension bar is released.  Something is different this time.

The second stage was clearly rotating at separation for this launch as well.

Yes, there were a couple of bright objects moving across the field of view during the deployment.  (I think they were bright stars or planets).  One in particular appears a few seconds after the satellite stack drifts out of view.  From the rate of motion, it looks like the second stage and stack were tumbling end-over-end at a few RPM.  Differential velocity (the sats at the top of the stack moving faster than those at the bottom of the stack) should cause them to separate quickly.

The SpaceX comment in the video was that the sats were designed to withstand low energy bumps if they happened to contact each other during deployment, not that such collisions were intentional or part of the planned deployment mechanism.

[rsdavis9]

I'm sure releasing the tension bars causes a spring like motion which then propells and spreads the sats away from the stage and eachother. Just a guess but it seems pretty logical, things under tension just tend to spring back once thetension is released.

You may be right, but that's not what SpaceX thought on the previous launch.  They were very deliberate in spinning the second stage and explained that this would provide the necessary differential momentum.  Maybe there are small springs between the satellites that are released at the time the tension bar is released.  Something is different this time.

The second stage was clearly rotating at separation for this launch as well.

Aha!  You are right.  It's not rotating as rapidly as last time, but there is a spin there.  Also not much background to view it against.  Ok, I retract my observation.

The only background I saw was the earth terminator. It very slowly was moving upwards in the shot. Do we know the terminator movement wasn't from the rotation around the earth?

[gongora]

So the network topology they're going for with the current iteration is akin to bent-pipe reflectors taking between users and ground stations? And that's the version that's going to go live for northern US and parts of Canada next year? How many ground stations do they have set up now?

6 Ku-band, 5 Ka-band in the US.
https://forum.nasaspaceflight.com/index.php?topic=48981.msg1990162#msg1990162