Author Topic: VKD-45a Russian Spacewalk (Dec 11th, 2018)  (Read 27334 times)

Offline Artyom.

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Re: VKD-45a Russian Spacewalk (Dec 11th, 2018)
« Reply #320 on: 12/13/2018 05:37 am »

Several photos, which were sent by cosmonaut Sergey Prokopyev.


Pictures taken by Alex Gerst.
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Offline jacqmans

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Re: VKD-45a Russian Spacewalk (Dec 11th, 2018)
« Reply #321 on: 12/13/2018 02:06 pm »

Offline jacqmans

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Re: VKD-45a Russian Spacewalk (Dec 11th, 2018)
« Reply #322 on: 12/13/2018 02:08 pm »

Offline jacqmans

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Re: VKD-45a Russian Spacewalk (Dec 11th, 2018)
« Reply #323 on: 12/13/2018 02:08 pm »

Offline CorvusCorax

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Re: VKD-45a Russian Spacewalk (Dec 11th, 2018)
« Reply #324 on: 12/13/2018 05:18 pm »
Departing Cygnus, Spx-16 dragon, various released cubesats, Spx-DM1 commercial crew demonstration and Upcoming Spx17 resupply, as well as the departing Soyuz with crew will all have to traverse the expanding VKD-45a debris cloud in the coming days and weeks.

Is that going to be a problem?
From up-thread:
Seeking correction from our forum experts:

The debris has low density and high surface area/mass ratio.  Such debris will decay well below ISS altitude in hours or days, and decay out of orbit in weeks or months.

That may be a rationalization, but it may serve as justification, too.
***

My new question: Is any of the debris being "discovered" and having a satellite ID # assigned and TLEs generated?

(Remembering Heidemarie Stefanyshyn-Piper's lost tool bag from EVA-1 on STS-126, November 18, 2008.)

I doubt, flakes of insulation material would show up on radar. They are also going to descent to lower orbits quickly, so no danger to ISS itself. But visiting vehicles by definition come from below, so their phasing orbits are goung to be in the orbits where the gunk is goung to end up. Luckily, its going to be low relative speeds of dozends, maximum hundreds of meters per second, and the debris is very fluffy. Should not cause critical damage to anything, but ... might get some people at NASA with micrometeorite-damage-paranoia worried.

Offline zubenelgenubi

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Re: VKD-45a Russian Spacewalk (Dec 11th, 2018)
« Reply #325 on: 12/13/2018 09:05 pm »
Departing Cygnus, Spx-16 dragon, various released cubesats, Spx-DM1 commercial crew demonstration and Upcoming Spx17 resupply, as well as the departing Soyuz with crew will all have to traverse the expanding VKD-45a debris cloud in the coming days and weeks.

Is that going to be a problem?
From up-thread:
Seeking correction from our forum experts:

The debris has low density and high surface area/mass ratio.  Such debris will decay well below ISS altitude in hours or days, and decay out of orbit in weeks or months.

That may be a rationalization, but it may serve as justification, too.
***

My new question: Is any of the debris being "discovered" and having a satellite ID # assigned and TLEs generated?

(Remembering Heidemarie Stefanyshyn-Piper's lost tool bag from EVA-1 on STS-126, November 18, 2008.)

I doubt, flakes of insulation material would show up on radar. They are also going to descent to lower orbits quickly, so no danger to ISS itself. But visiting vehicles by definition come from below, so their phasing orbits are goung to be in the orbits where the gunk is going to end up. Luckily, its going to be low relative speeds of dozens, maximum hundreds of meters per second, and the debris is very fluffy. Should not cause critical damage to anything, but ... might get some people at NASA with micrometeorite-damage-paranoia worried.

The ISS schedule has no Visiting Vehicles launching until January 18 at the earliest (SpX-DM1).  Past that, the next VVs arrive in February and/or March.  I >assume< the debris will have decayed from orbit by then.

It may be a moot point--THIS time--because there won't be any ISS-bound vehicles to potentially endanger.
« Last Edit: 12/13/2018 09:07 pm by zubenelgenubi »
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Offline jacqmans

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Re: VKD-45a Russian Spacewalk (Dec 11th, 2018)
« Reply #326 on: 12/14/2018 12:51 pm »

Offline jacqmans

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Re: VKD-45a Russian Spacewalk (Dec 11th, 2018)
« Reply #327 on: 12/14/2018 12:52 pm »

Online Lar

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Re: VKD-45a Russian Spacewalk (Dec 11th, 2018)
« Reply #328 on: 12/15/2018 08:31 pm »
The ISS schedule has no Visiting Vehicles launching until January 18 at the earliest (SpX-DM1).  Past that, the next VVs arrive in February and/or March.  I >assume< the debris will have decayed from orbit by then.

It may be a moot point--THIS time--because there won't be any ISS-bound vehicles to potentially endanger.
Maybe that was taken into account when this was scheduled.
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Offline zubenelgenubi

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Re: VKD-45a Russian Spacewalk (Dec 11th, 2018)
« Reply #329 on: 12/15/2018 10:42 pm »
The ISS schedule has no Visiting Vehicles launching until January 18 at the earliest (SpX-DM1).  Past that, the next VVs arrive in February and/or March.  I >assume< the debris will have decayed from orbit by then.

It may be a moot point--THIS time--because there won't be any ISS-bound vehicles to potentially endanger.
Maybe that was taken into account when this was scheduled.

Yes, I concur.  This EVA occurred near or in the high-beta cut-outs that occur near the solstices that restrict dockings and berthings to ISS, yes?
***

As a larger issue, I'm interested in how planning for this EVA occurred.  And, what the reaction on the USOS side was as plans progressed.  If anyone from NSF can learn anything...

Given the circumstances, I'm not holding my breath. ::)
***

I'd also be interested, weeks or months down the road, to learn if anything useful is discovered during the sample analysis.
« Last Edit: 12/15/2018 10:43 pm by zubenelgenubi »
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Offline Bob Shaw

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Re: VKD-45a Russian Spacewalk (Dec 11th, 2018)
« Reply #330 on: 12/15/2018 11:27 pm »
Any debris will either decay quickly or be co-orbital, posing at most a 'firefly' risk when illuminated by laser rangefinding - but that's not terribly likely.

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