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#100
by
JimO
on 15 Nov, 2011 17:25
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It's just the perigee that seems to be ascending. The apogee is coming down even faster and the mean altitude with it. Just what is causing the perigee behavior isn't clear, though outgassing or attitude thruster firings have been suggested. There's also some slight possibility that the orbital elements coming out of Space Command are in error -- I think that's unlikely, though it's happened before.
"Seems" is the operative verb, here.
The originator of the theory of slight orbit rise, ted molczan, is now much less convinced the rise is real, then when he first suggested it a few days ago. He suspects it may be associated with NORAD assumptions of drag coefficients used in projecting the orbit forweard. Or it might be real.
And Roskosmos has not said a word about the allegations, despite the russian news media being full of the claims -- usually reported as fact, rather than the supposition of one very skilled -- and cautious -- high-quality amateur analyst.
As with so much else about this mystery mission, it remains less than certain fact.
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#101
by
JimO
on 15 Nov, 2011 17:29
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This, to me, is the central question needing expert attention.
http://www.planetary.org/blog/article/00003261 Jim Oberg - 11/15/2011 - 05:31 // Can somebody with interplanetary navigation and targeting experience comment on the effect of the parking orbit's shifting day by day [about 6 degrees per day], out of proper alignment for the trans-Mars burn, and what that implies for the REAL chance of re-starting this mission? This has nothing to do with the 'launch window' based on Earth-Mars relative orbital positions.
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#102
by
Jim
on 15 Nov, 2011 17:33
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A "mission satisfaction telemetry kit" that transmits and records a series of environmental measurements at and around the payload interface.
A reradiating antenna in the PLF to allow a spacecraft transmitter to send telemetry.
Up to two channels of serial data from the spacecraft that can be transmitted at a maximum rate of 2kbps.
All are kits. I'd assume other vehicles are typical, but I don't have the manuals handy (though if anyone is interested, L2 has a fantastic collection!).
--N
"option1" provides no spacecraft telemetry or status, it only provides ascent environmental data.
As for the others, isnt that what I said.
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#103
by
Jim
on 15 Nov, 2011 17:36
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Russia's manned space launch system and experience in EVAs CAN be put to work here to save Phobos-Grunt! Send a Soyuz up to check it out and attempt repairs. Bold, sure, but why just abandon P-G by doing nothing, and thus risk ending Russia's planetary program for yet another decade?
Russia's reputation would be enhanced by a rescue mission even if it didn't succeed. NASA has offered any possible help, and can offer much advice from shuttle satellite repairs, etc. "Just do it!"
Utterly ridiculous! Not bold
Wrong, Soyuz can't not support a repair mission. Nor is any manned mission going to approach a vehicle where there is no insight into its status.
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#104
by
Jim
on 15 Nov, 2011 17:40
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U but no technical barriers
Art Harman, Director, The Coalition to Save Manned Space Exploration http://SaveMannedSpace.com
Wrong, there are many show stoppers. I am going to use the "I" word. it is impossible. I
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#105
by
Chris Bergin
on 15 Nov, 2011 17:41
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not to mention that the current version of Soyuz spacecraft does not have any EVA capabilities. Lets stop this futile effort of speculation and whatiffing.
Concur.
Ok, folks. Back on track. Let's keep it within the corridor of the efforts to restore PB only.
Let's keep this thread tidy and to the level expected on NSF.
(Or lose your posts - seen as three people ignored this).
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#106
by
iamlucky13
on 15 Nov, 2011 19:09
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This, to me, is the central question needing expert attention.
http://www.planetary.org/blog/article/00003261
Jim Oberg - 11/15/2011 - 05:31 // Can somebody with interplanetary navigation and targeting experience comment on the effect of the parking orbit's shifting day by day [about 6 degrees per day], out of proper alignment for the trans-Mars burn, and what that implies for the REAL chance of re-starting this mission? This has nothing to do with the 'launch window' based on Earth-Mars relative orbital positions.
I've also been hoping someone with sufficient knowledge on interplanetary trajectories could provide at least educated speculation, if not a knowledgeable answer.
And also, it would be helpful to take a step back and provide some background info for a few of us:
What exactly are we talking about here - sidereal angle of the orbital plane (as the intersection line with the ecliptic) or something else?
What drives the change? The earth revolving around the sun is about 1 degree per day, not 6. The earth-Mars angle I'd expect to change at about half that rate.
Or are we talking about the departure angle relative to the existing sidereal angle in order to make up for the changing final aim point...to be loose with terms
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#107
by
JimO
on 15 Nov, 2011 19:52
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The orbital plane precesses about 6 degrees per day in geocentric reference because of Earth's equatorial oblateness. So the geocentric plane of the departure asymptote is sweeping across the celestial sphere at some combination of this rate, earth's axial tilt, and Earth's movement around the sun.
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#108
by
JimO
on 15 Nov, 2011 19:54
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If it becomes necessary to interdict the satellite before it hits the atmosphere, the Russian Defense Ministry has available a totally new military command, the 'Aerospace Defense Troops', which formally come into being on December 1. To ask for US help in smashing the satellite to safe smithereens would be a humiliating confession that the Russian defense forces are incapable of providing this service.
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#109
by
Lee Jay
on 15 Nov, 2011 20:11
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Is it more humiliating to fail yourself or to ask for help and succeed?
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#110
by
Rocket Science
on 15 Nov, 2011 20:15
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China can do it, problem solved…
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#111
by
BeanEstimator
on 15 Nov, 2011 20:56
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If it becomes necessary to interdict the satellite before it hits the atmosphere, the Russian Defense Ministry has available a totally new military command, the 'Aerospace Defense Troops', which formally come into being on December 1. To ask for US help in smashing the satellite to safe smithereens would be a humiliating confession that the Russian defense forces are incapable of providing this service.
somebody, somewhere, had linked to the space review article on analysis of liability which discussed ASAT options.
we can do it, china can do it, or the russians can do it. however if they do it, they risk exposing their asat capabilities (or lack thereof)
The former Soviet Union did possess a co-orbital ASAT capability with its Istrebitel ASAT system, but it is uncertain whether they ever had or presently possess a direct-ascent ASAT system capable of performing an intercept of Phobos-Grunt. An intercept could be performed by an ABM system as was demonstrated by the ancillary use of components of the United States’ ABM system. However, it is unclear what ABM capabilities the Russian Federation has aside from the Cold War era Gazelle (SH-08/ABM-3) missiles, which surround Moscow. It is unlikely that these missiles, which originally carried a 10-kiloton nuclear warhead, have the capability to precisely target Phobos-Grunt as it orbits above.http://www.thespacereview.com/article/1968/1its always more humiliating to ask for help and succeed. especially in aerospace and defense. ego's and pride are at risk.
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#112
by
Archibald
on 15 Nov, 2011 21:18
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If it becomes necessary to interdict the satellite before it hits the atmosphere
A $120 million Mars probe turned into an ABM target. Sometimes reality is much, much weirder than anything a sci-fi writter would ever imagine (sigh...)
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#113
by
Michael J
on 15 Nov, 2011 21:32
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If it becomes necessary to interdict the satellite before it hits the atmosphere, the Russian Defense Ministry has available a totally new military command, the 'Aerospace Defense Troops', which formally come into being on December 1. To ask for US help in smashing the satellite to safe smithereens would be a humiliating confession that the Russian defense forces are incapable of providing this service.
somebody, somewhere, had linked to the space review article on analysis of liability which discussed ASAT options.
we can do it, china can do it, or the russians can do it. however if they do it, they risk exposing their asat capabilities (or lack thereof)
The former Soviet Union did possess a co-orbital ASAT capability with its Istrebitel ASAT system, but it is uncertain whether they ever had or presently possess a direct-ascent ASAT system capable of performing an intercept of Phobos-Grunt. An intercept could be performed by an ABM system as was demonstrated by the ancillary use of components of the United States’ ABM system. However, it is unclear what ABM capabilities the Russian Federation has aside from the Cold War era Gazelle (SH-08/ABM-3) missiles, which surround Moscow. It is unlikely that these missiles, which originally carried a 10-kiloton nuclear warhead, have the capability to precisely target Phobos-Grunt as it orbits above.
http://www.thespacereview.com/article/1968/1
its always more humiliating to ask for help and succeed. especially in aerospace and defense. ego's and pride are at risk.
That is my article and analysis. I've been watching this thread and the proceeding one very carefully since the launch, and I am impressed with the quality of information being passed along, so much so that I've tweeted the URL to this thread and its predecessor to my Twitter followers.
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#114
by
Patchouli
on 15 Nov, 2011 21:33
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China can do it, problem solved…
The vehicle is not made for on orbit repair.
Pretty much all you could do from a Shenzhou is try and see if some sequencer switch had not been tripped as in SYNCOM IV-3 during STS-51-D.
If it's a more serious problem it cannot return the probe the only vehicles that could do that were the Shuttle or Buran and even then you'd need some sorta jig to place it into.
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#115
by
Michael J
on 15 Nov, 2011 21:37
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China can do it, problem solved…
The vehicle is not made for on orbit repair.
Pretty much all you could do from a Shenzhou is try and see if some switch had not been tripped as in SYNCOM IV-3 during STS-51-D.
If it's a more serious problem it cannot return the probe the only vehicles that could do that was the Shuttle or Buran and even then you'd need some sorta jig to place it into.
I think he was talking about China intercepting PG with it direct-ascent ASAT capability.
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#116
by
kevin-rf
on 15 Nov, 2011 21:43
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Shooting it down (regardless of who does it) will be a PR nightmare. If the US or China does it, it will be viewed by the Russian populace as saber rattling and an attempt to crush Russia's mars dreams. If Russia does it, it is an admission of failure and they did something unsafe and now have to throw a hail marry. And if the Russian's miss? I am dreading the scorched earth fallout that will be all that remains of the Russian Space Program.
I can not see it being shot down.
Also, just because the US and China have recently hit a bullet with a bullet does not mean they have a system that can take out any ole sat in LEO. Remember the missile that hit USA-193 was a "modified" missile that had to be prepared months in advance. It is also worth noting that at the time of the Chinese successful ASAT test, there was also stories in the press about other tests where they did not hit the target. China is not 1 for 1.
My point being the other "ASAT" assets are mostly likely not off the shelf solutions . While a valid option I rank it up there with Clint Eastwood riding a Soyuz to wrangle it to Mars!
...and then we also have to worry about that dang calibration source. For some reason I doubt it is designed to fully disperse on reentry. Meaning someone "could" find it and get hurt.
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#117
by
Rocket Science
on 15 Nov, 2011 21:47
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#118
by
Patchouli
on 15 Nov, 2011 21:54
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I wonder if shooting it down may put ISS at risk as some of the debris could possibly end up in a higher orbit.
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#119
by
gregzsidisin
on 15 Nov, 2011 21:55
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As with so many others here, I find this very disheartening - but sadly unsurprising. It seems clear the Russians tried to do too much with too few resources. There were so many failure modes over the long mission to begin with; unfortunately, they may have been thrown off the horse right out of the chute.
Short of their restoring communications and control, AND being somehow able to successfully launch for Mars, the ideal scenario would be building F-G #2 for the next window, doing more testing, and taking to heart lessons learned.
That seems too logical to be possible in real life, doesn't it...?
