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#960 by JimO on 07 Dec, 2011 14:00
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ESA has agreed to THREE more days of comm attempts, to command the engines to fire. Practically any attitude of firing will be an improvement, in that most random burns will result in rapid decay.
I suspect the speculation on ESA's motives [EXOMARS] is right on.
But why are they the supplicants, seeking favors? Sadly, Russia's track record would seem to suggest that they are the ones needing to earn their way onto the project -- but then, big boosters remain their aces in the hole, and they play those cards well.
ЕКА попытается послать "Фобос-Грунту" сигналы на включение двигателей
16:09mt 07/12/2011
http://www.ria.ru/science/20111207/509319097.html
Европейская станция слежения предприняла новые попытки связи со станцией "Фобос-Грунт"
07 декабря 2011 года 16:54mt
http://www.interfax.ru/politics/news.asp?id=220642
Wednesday's passes began at 10:30gmt and 12:00gmt, "results not yet known".
"В четверг [Thursday] у европейских специалистов будет два "окна" для связи с "Фобосом" - с 14.20 по 14.30 и с 15.54 по 16.01 мск [GMT+4]. Следующие "окна" в пятницу [Friday] - с 14.11 по 14.20 и с 15.45 по 15.52 мск [GMT+4]." -
#961 by Ben the Space Brit on 07 Dec, 2011 14:10
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In fairness to Roscosmos, I can't blame them for not wanting to give up on what is effectively a Flagship-class mission. Additionally, being able to halt what would otherwise be the uncontrolled descent of essentially a very large bomb is a desirable objective.
Re.: The Russian boosters: Does Ariane-5 have any TMI capability? Given that it can boost two average-sized comsats to GTO, I'm sure it must have some capability. Personally, I suspect that this is more to do with keeping the flow for Soyuz-ST going. -
#962 by STS-200 on 07 Dec, 2011 15:00
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Re.: The Russian boosters: Does Ariane-5 have any TMI capability? Given that it can boost two average-sized comsats to GTO, I'm sure it must have some capability.
Theoretically yes it has significant TMI ability, 5-6t depending on the alignment of Mars. However, the upper stage can't (currently) be restarted which significantly limits launch flexibilty and means those launch opportunities that do exist are instantaneous. -
#963 by robertross on 07 Dec, 2011 15:03
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ESA has agreed to THREE more days of comm attempts, to command the engines to fire. Practically any attitude of firing will be an improvement, in that most random burns will result in rapid decay.
I suspect the speculation on ESA's motives [EXOMARS] is right on.
But why are they the supplicants, seeking favors?
Perhaps reducing the risk that the spacecraft doesn't land in their back yards. Nothing to lose at this point really (except incurred costs) -
#964 by baldusi on 07 Dec, 2011 15:06
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Re.: The Russian boosters: Does Ariane-5 have any TMI capability? Given that it can boost two average-sized comsats to GTO, I'm sure it must have some capability. Personally, I suspect that this is more to do with keeping the flow for Soyuz-ST going.
Ariane-5 has wonderful TMI capability. They can do 7t to TLI, for example. And the ME version will even improve at that. The small issue is that it might cost something like 200M/launch. And they might be supply constrained already for their commercial missions. In particular, the ExoMars mission sort of falls in the transition to ME. So it's both risky to use the "new" launcher, and they might be further constrained from the current ECA batch and the commercial commits, as they do the ME transition.
I seriously doubt that the Russians would stop the Soyuz-ST program. The Europeans are practically paying for the Soyuz-2 transition, and almost every worker outside of MCC is Russian, they they are getting most of the surplus, too. Nope, I guess ESA is wanting to be "nice" for the ExoMars. -
#965 by baldusi on 07 Dec, 2011 15:08
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Arianespace usually proposes the ES stage for those missions. Granted, it would have less performance. But significant performance none the less.Re.: The Russian boosters: Does Ariane-5 have any TMI capability? Given that it can boost two average-sized comsats to GTO, I'm sure it must have some capability.
Theoretically yes it has significant TMI ability, 5-6t depending on the alignment of Mars. However, the upper stage can't (currently) be restarted which significantly limits launch flexibilty and means those launch opportunities that do exist are instantaneous. -
#966 by Chris Bergin on 07 Dec, 2011 15:10
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My home page has been updated with a lot of news and background on Fobos-Grunt and other space events and trends.
http://www.jamesoberg.com/
That's very useful, as it's so easy to lose track on these large threads.
And thanks for the links too
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#967 by bolun on 07 Dec, 2011 15:14
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Re.: The Russian boosters: Does Ariane-5 have any TMI capability? Given that it can boost two average-sized comsats to GTO, I'm sure it must have some capability. Personally, I suspect that this is more to do with keeping the flow for Soyuz-ST going.
Ariane-5 has wonderful TMI capability. They can do 7t to TLI, for example. And the ME version will even improve at that. The small issue is that it might cost something like 200M/launch. And they might be supply constrained already for their commercial missions. In particular, the ExoMars mission sort of falls in the transition to ME. So it's both risky to use the "new" launcher, and they might be further constrained from the current ECA batch and the commercial commits, as they do the ME transition.
I seriously doubt that the Russians would stop the Soyuz-ST program. The Europeans are practically paying for the Soyuz-2 transition, and almost every worker outside of MCC is Russian, they they are getting most of the surplus, too. Nope, I guess ESA is wanting to be "nice" for the ExoMars.
It is time to be "nice".
http://spaceflightnow.com/news/n1111/30marsprogram/QuoteEuropean space officials formally invited Russia to participate in the ExoMars program in October, specifically requesting a Proton rocket to launch the 2016 orbiter. Roscosmos has until January to respond, but Russian officials will meet with NASA and ESA managers in Paris on Dec. 7 for a two-day summit on a potential trilateral Mars exploration initiative.
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#968 by Michael J on 07 Dec, 2011 15:27
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Quote
In fairness to Roscosmos, I can't blame them for not wanting to give up on what is effectively a Flagship-class mission. Additionally, being able to halt what would otherwise be the uncontrolled descent of essentially a very large bomb is a desirable objective.
But yet they publicly play-down the debris and hydrazine risks. It is notable in the article from Ria Novosti that I posted, it mentioned (taking into account Google translations) that they want to try and get it into a higher orbit so that they have more time to try and regain control. Interestingly, NASA's chief space debris scientist has publicly stated via The Space Show that Phobos-Grunt's propellant does not present the same risks as USA-193.
A link to an article I wrote based on the show: http://www.examiner.com/space-policy-in-national/nasa-space-debris-chief-phobos-grunt-poses-no-threat
Here is a link to the December 5th interview on The Space Show: http://www.thespaceshow.com/detail.asp?q=1666 -
#969 by JimO on 07 Dec, 2011 16:53
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Interestingly, NASA's chief space debris scientist has publicly stated via The Space Show that Phobos-Grunt's propellant does not present the same risks as USA-193.
I'm completely willing to defer to Nick Johnson's judgment here, and have elsewhere fiercely defended him against his critics in the case of the USA-193 entry survival analysis. Whatever he states about the Ph-G entry hazard is gospel for me. -
#970 by bolun on 07 Dec, 2011 16:57
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ESA returns.Quote
esaoperations ESA Operations
Following request from #PhobosGrunt mission managers, ESA is providing tracking support this week via #Maspalomas station. Details later
1 hour ago
From http://twitter.com/esaoperations -
#971 by olasek on 07 Dec, 2011 17:34
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It's good to know the programs under NASA's watch are well funded and properly managed....like JWST
Or like Hubble
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#972 by bolun on 07 Dec, 2011 19:09
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ESA returns.
Quoteesaoperations ESA Operations
Following request from #PhobosGrunt mission managers, ESA is providing tracking support this week via #Maspalomas station. Details later
1 hour ago
From http://twitter.com/esaoperationsQuoteesaoperations ESA Operations
Brief update on this week's additional tracking support to #PhobosGrunt now online http://www.esa.int/ops
1 hour ago
ESA responds to Phobos-Grunt tracking request
7 December 2011
Following a request from Russian mission authorities, ESA is continuing its efforts to communicate with Phobos Grunt via the Agency's 15 m-diameter Maspalomas tracking station located in Spain. Communication attempts on Monday, Tuesday and today, which made use of a redundant transmitter on board the spacecraft, did not succeed. The Agency has agreed to continue the effort until Friday, 9 December.
http://www.esa.int/SPECIALS/Operations/SEM3T55XPVG_0.html -
#973 by JimO on 07 Dec, 2011 22:25
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Lavochkin's General Director and General designer, Viktor Khartov, talks to Izvestia.
«Фобос-Грунт» был кавалеристским наскоком
7 декабря 2011, 17:58 | | Иван Чеберко
http://www.izvestia.ru/news/508997
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#974 by olasek on 07 Dec, 2011 23:50
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«Фобос-Грунт» был кавалеристским наскоком
At least the fellow doesn't hide that the whole endeavour was like playing a Russian roulette. Too bad this expensive "lesson" doesn't yet include data what was the root cause of the failure. -
#975 by Michael J on 08 Dec, 2011 12:03
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The most recent article from Ria Novosti: ESA communications attempts fail; spacecraft expected to reenter around January 10th.
(Google translated): http://translate.google.com/translate?hl=en&sl=ru&tl=en&u=http://ria.ru/science/20111207/509492824.html -
#976 by Moskit on 08 Dec, 2011 12:05
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http://www.izvestia.ru/news/508997
This is the best view on situation I've read so far!
Rought translation (with some sections ommited):
Every mission has three parameters: complexity, resources and risks. If we ask someone to send a complicated mission with little risk, it will involve huge resource. If you plan to send a mission to Mars in such a way, you would first test hardware on Earth orbit, then Lunar orbit, then model all aspects of the target mission. With F-G situation was a bit different - we did not fly to other planets for 25 years. There was a huge amount of new hardware without flight history. Practically only fuel tanks from Fregate were previously flown.
Project itself was very complex, with a large number of instruments and many algorithms.
Maximum complexity and minimum resources translated to maximum risks.
It was decided the risk is ok to fly F-G. Apparently we stumbled right in the beginning of the flight. F-G flew well for two hours after the launch. It turned itself on, extended elements (solar panels), orientated to Sun and began to receive energy. It turned on all required hardware, and Chinese satellite. It was all confirmed by telemetry. And then... it flew out of Russian zone of communication. Burn did not happen.
Our communication stations are designed for deep space and could not track fast-moving object in low orbit long enough to complete long link establishment procedures.
In the beginning we could not target the satellite. It was tracked only by ground means, and position was inaccurate, calculated up to 6 degrees. That's why us, and European stations had to add modified antennas emiting wide beams. As a result we had a few sessions and received some telemetry.
It said that radio module works, link with onboard computer is up. Photos of on-orbit F-G showed that it was not tumbling, meaning Sun orientation module worked correctly.
We do not know when and why burn sequence was aborted. There could be many hypothesis, but fact is only one: F-G is Sun-orientated, onboard computer fulfills its function.
Logic says that when sequence is aborted, F-G will await commands from ground. Apparently it is still in that mode and we will continue attempts to make it alive.
As for the failure, there are many possibilities. For example it could be a programming error that could not be detected during modelling on Earth. Difference between model and real situation could be large enough to "stupify" computer.
It could have also been a hardware problem. Before we lost contact with F-G we enabled power to several modules, and theoretically damage during launch (?) might have caused problems with power supply.
But those are all working versions, official reason should be established by appropriate commission.
As far as we know the rocket worked nominally. However we think that launcher should have been chosen differently, not Zenit, but Proton, which could take F-G directly to required orbit. Then F-G could be turned on and verified module by module, new comms line would be tested, and trajectory corrections made.
Decision about launcher was taken in 90s, and project was based on that.
F-G was a sort of jumping forward (cavalry charge?) over 25 years gap. It was understood that risk was high, but imagine if it were a success! However it is necessary to work step by step, systematically. That's why we should go back to Lunar exploartion.
....
I would not get fixated on F-G. We have many projects. This year we launched Electro-L, a new generation sat. Our Fregat boosters have done their job on 8 launches from 3 locations, with one more launch from each location by end of this year. -
#977 by notsorandom on 08 Dec, 2011 12:15
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Thank you for that translation Moskit! That was very informative.
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#978 by JohnFornaro on 08 Dec, 2011 13:52
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Quote
Every mission has three parameters: complexity, resources and risks.
Faster, better, and cheaper? Pick any two? -
#979 by Jason1701 on 08 Dec, 2011 16:50
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Quote
Every mission has three parameters: complexity, resources and risks.
Faster, better, and cheaper? Pick any two?
Or, in P-G's case, one.
