SpaceX F9 : Starlink v0.9 : May 23, 2019 - DISCUSSION

[speedevil]

Even with a feathered solar panel, drag at 440 km altitude is significantly higher than at the operational altitude.

Not if that operational altitude is 340km, for which they are also designed.

[Comga]

I would like to show some graphs by Hugo, a member of the german forum raumfahrer.net. I asked for his consent to show them here.

Link to the thread

https://www.raumfahrer.net/forum/smf/index.php?topic=13231.msg456752#msg456752

Curious numeric
In the Mehrfachgrafik image with color classifications, 3 objects are red (no propulsive maneuvers) 3 are orange (not yet to constellation orbit) 3 are yellow, (final orbit but no slot) and 3 are blue. (Dropped orbit potentially for deorbit)
It seems too orderly to be random, like they planned to treat trios of satellites differently, such as for drifting a few into another plane. 

[gongora]

It's one plane.  Some satellites had problems.  A couple may have been chosen in advance for deorbit testing.

[envy887]

It's one plane.  Some satellites had problems.  A couple may have been chosen in advance for deorbit testing.

It does look like 3 are dead and decaying, 3 are actively deorbiting, and 3 are not at the operational orbit but still under control and maintaining altitude, which must meant they are testing something.

[Comga]

It's one plane.  Some satellites had problems.  A couple may have been chosen in advance for deorbit testing.

That doesn’t at all contradict what I wrote
Of course they were all launched into one plane.
Some failed. There are debris including the second stage.
“Coincidence is not causality.”
1 out of 36 times you roll a pair of ones.
But 3-3-3-3 is curious

[intelati]

https://twitter.com/planet4589/status/1162605103142113280

No change in Starlink satellite orbital heights for last week or so. Object AV [44] still in low 312 x 348 km orbit (and reported by Jay Respler to be 2nd magnitude)

I was going to say, the middle portion That are stuck around 430km are waiting for something. A test or plane change. I really don't know. I hope we get an update on them during the next launch

[gongora]

I was going to say, the middle portion That are stuck around 430km are waiting for something. A test or plane change. I really don't know. I hope we get an update on them during the next launch

Those are the ones that failed early.

[Comga]

I was going to say, the middle portion That are stuck around 430km are waiting for something. A test or plane change. I really don't know. I hope we get an update on them during the next launch

Those are the ones that failed early.

No, not THEM
Several of the satellites have paired or tripled up at other altitudes, some in orbits near the deployment altitude.
Those scattered just below the operational altitude look like failed propulsion units. All moves upward. No change for a long time
But at least two are paired below that, rising up from even lower altitudes.
The one that descended to just above the deployment altitude would match the differential precession (with respect to the constellation) of the ones that stayed at the deployment altitude.
Many of the others seem to be going to specific altitudes 

[GWR64]

A general question I would have:
Are there considerations that operators of large Satellite constellations, publish TLE data of their satellites should?
Starlink, OneWeb, Amazon, Telesat ...
NORAD will one day reach its limits.
In addition, the publication of the NORAD-TLE is in my opinion a voluntary achievement.

[envy887]

I was going to say, the middle portion That are stuck around 430km are waiting for something. A test or plane change. I really don't know. I hope we get an update on them during the next launch

Those are the ones that failed early.

The 3 that failed early are slowly but steadily decaying. The rest are all either moving up, moving down, or actively holding altitude (not decaying at all) meaning they are all under control.

[gongora]

I think Planet may be the only constellation publishing their positions so far.  It's not required.  The constellations sharing frequencies will eventually need good information on where everybody is, so they will probably be sharing among themselves even if they don't make it public.

[gongora]

Jonathan McDowell posted some new Starlink plots on Twitter

https://twitter.com/planet4589/status/1166558337288298496

A summary of visual brightness  observations of individual Starlink satellites reported on Seesat-L (http://satobs.org) in July-August. Blue: operational sats. Red:  non-op sats in lower orbits. Green: debris. Vertical bars: sats with no brightness estimates.

Thanks to observers Jay Respler, Brad Young, @cgBassa, Bram Dorreman, and Ron Lee for their data.

I have provided as-observed magnitudes rather than deriving so-called 'standard mag' needed for future predictions - I wanted to show what people are typically seeing in actuality.

Note that almost all the individual satellites have been observed at least once. Range from mag 4 to 7 seems typical.  This should be representative of the operational constellation modulo any design changes to reduce albedo.

For comparison here are the current apogees (upward pointing triangles) and perigees (downward) for each satellite in the same colour scheme (blue operational, red not, green debris)

Trivial correction to last plot (44249 is non-operational)

[cscott]

The groups of three could be hardware-related; ie they built every specific hardware configuration at least three times, so as to be sure to distinguish assembly/one-off issues from actual issues specific to the hardware configuration. In that case, the fact that groups of three are staying together indicates that the manufacturing/assembly is solid/repeatable, although some of the assembled configurations didn't work out in practice.

[Rondaz]

5 months in and 5 satellites deorbiting - already a near disaster. 2400 planned deorbits per year will be impossible to manage. Will there be any regulation / safety standards inquiry...or will the
@fcc wait until an actual collision?

https://twitter.com/greg_wyler/status/1168988584818425857

[Rondaz]

Some additional bits of useful information about #Aeolus/#Starlink from SpaceX:

- Starlink 44 is operational and capable of avoidance maneuvers if necessary

- In three months the Starlink fleet has performed 16 collision avoidance maneuvers without any manual input (!)

https://twitter.com/Astro_Jonny/status/1168976820349415430

[Rondaz]

Holger Krag, head of ESA SAO praises SpaceX handling of Aeolus maneuvering in German publication..

TUESDAY, 03. SEPTEMBER 2019
Collision in space prevents Esa satellite flying around SpaceX satellites

https://www.n-tv.de/wissen/Esa-Satellit-umfliegt-SpaceX-Satelliten-article21248848.html

[Rondaz]

Over lunch, did my own sims of the #SpaceX 44 & @esa #Aeolus encounter with newer TLEs - got close over many orbits to 4.1 km..

https://twitter.com/DrChrisBridges/status/1169223480379944960

[marsbase]

5 months in and 5 satellites deorbiting - already a near disaster. 2400 planned deorbits per year will be impossible to manage. Will there be any regulation / safety standards inquiry...or will the
@fcc wait until an actual collision?

https://twitter.com/greg_wyler/status/1168988584818425857

I probably don't need to say this but just in case:  At least 3 SpaceX satellites are being deorbited intentionally as proof of concept.  If there are 2 more, they may be defective but that ratio of bad sats can't be extrapolated to an entire constellation because this was only V0.9 and because SpaceX was testing a number of configurations.  These are not the final form of Starlink sats.

 I even read one headline saying that the ESA had dodged a constellation of SpaceX sats.  Clearly this has some political motivation aimed at people who are not familiar with what happened.  ESA maneuvered because they were coming close to 1 (one) SpaceX sat.  It is irrelevant that this sat was launched as part of a constellation because ESA was not near any of the other sats in the constellation.  They were only near the one in the lowest orbit.  None of the others ever come near the ESA sat.

[envy887]

5 months in and 5 satellites deorbiting - already a near disaster. 2400 planned deorbits per year will be impossible to manage. Will there be any regulation / safety standards inquiry...or will the
@fcc wait until an actual collision?

Wyler is not helping his own cause here.

And "near disaster" is total and complete FUD.

[soltasto]

I probably don't need to say this but just in case:  At least 3 SpaceX satellites are being deorbited intentionally as proof of concept.  If there are 2 more, they may be defective but that ratio of bad sats can't be extrapolated to an entire constellation because this was only V0.9 and because SpaceX was testing a number of configurations.  These are not the final form of Starlink sats.

 I even read one headline saying that the ESA had dodged a constellation of SpaceX sats.  Clearly this has some political motivation aimed at people who are not familiar with what happened.  ESA maneuvered because they were coming close to 1 (one) SpaceX sat.  It is irrelevant that this sat was launched as part of a constellation because ESA was not near any of the other sats in the constellation.  They were only near the one in the lowest orbit.  None of the others ever come near the ESA sat.

Greg Wyler is the Founder & Chairman of OneWeb and it's quite clear that he is playing every possible card but competition to get SpaceX out of the Internet satellite business while ESA is seeking funding for their automated collision avoidance system, so it's not really a surprise. Most of the media also blow things out of proportion as it gets them more clicks. Kinda depressing to be honest