Author Topic: Fobos-Grunt Troubleshooting Latest (Part 2) (Read 647586 times)

Lee Jay · « **Reply #40 on:** 11/14/2011 06:53 pm »

Quote from: Pheogh on 11/14/2011 06:41 pm

Quote from: Svetoslav on 11/14/2011 06:32 pm
http://ria.ru/science/20111114/488740960.html

RIA Novosti reports that the crew of the ISS was not able to take pictures of Phobos-Grunt.

It's because the distance between P-G and ISS was too high- between 120-150 kms.

Has there been any published imagery from ground based observers, detailed imagery?

Not that I know of, but unless it's military, I don't think you're going to get detailed imagery of such a small target. This is about as good as you can hope for (ROSAT):

http://legault.perso.sfr.fr/rosat.html

JWag · « **Reply #41 on:** 11/14/2011 07:05 pm »

RussianSpaceWeb has some good information on the ground hardware used (so far) to attempt contact with P-G:

http://www.russianspaceweb.com/phobos_grunt_kik.html

It is not encouraging to read.

hop · « **Reply #42 on:** 11/14/2011 07:12 pm »

Ted Molczan is having second thoughts about the orbit changes being due to thrusters or venting: http://www.satobs.org/seesat/Nov-2011/0156.html

riney · « **Reply #43 on:** 11/14/2011 07:57 pm »

Assuming the Russians were to ask, are there any U.S. ground assets that could be made capable of contacting/commanding the spacecraft in the available time?

--riney

clongton · « **Reply #44 on:** 11/14/2011 08:05 pm »

Quote from: riney on 11/14/2011 07:57 pm

Assuming the Russians were to ask, are there any U.S. ground assets that could be made capable of contacting/commanding the spacecraft in the available time?

--riney

Without even knowing the source of the problem it would be difficult to even consider offering. If they are able to actually identify the source problem, then maybe, depending on what it is. Having said that, I think it is unlikely and that saddens me. I really want our Russian friends to score.

JimO · « **Reply #45 on:** 11/14/2011 08:06 pm »

My comments in all caps, to an email from a friend about Popovkin statements today:

> Hi, [FROM Constantine Domashnev] >
> A new official update on the Phobos Grunt/Ground status is here:
> http://roscosmos.ru/main.php?id=2&nid=18258 :: 14.11.2011
>
> A brief summary [mine] of Vladimir Popovkin’s statements:
>
> 1. The probe itself does not have design flows.
STATEMENT OF FAITH, NOT OF FACT. ALL MUCH-BALLYHOOED SOVIET ERA EXPERIMENTS IN 'REMOTE VIEWING' AND OTHER E-S-P WERE FAILURES, BUT PERHAPS POPOVKIN BELIEVES HE CAN PERFORM SUCH MIRACLES WITH HIS OWN MIND. ROSKOSMOS OFFICIALS HAVE A PATTERN OF VOICING THEIR DESIRED CONCLUSIONS TO ACCIDENT INVESTIGATION PANELS BEFORE THEY HAVE EVEN BEGUN DATA COLLECTION AND DELIBERATION – THIS IS CONSISTENT WITH THAT LONG, TOXIC TRADITION.

> However, a significant part of the problem is a narrow communication window
> (7 minutes) due to the probe’ unexpectedly close range / ultra low orbit.
SINCE THIS IS HOW THE COMMUNICATION SYSTEM WAS DESIGNED, HOW CAN STATEMENT 1-B BE PLACED DIRECTLY BELOW THE TOTALLY CONTRADICTORY 1-A?? HOW CAN ONE BELIEVE TWO MUTUALLY EXCLUSIVE 'FACTOIDS' SIMULTANEOUSLY?

> 2. Astronomically, the deadline for recovering the probe is early December.
MY INTERPLANETARY NAVIGATION GURUS TELL ME THAT DUE TO THE PRECESSION OF THE PROBE'S PARKING ORBIT, IT HAS ALREADY PASSED OUTSIDE ANY POSSIBLE SUCCESSFUL TRANS-MARS-INSERTION BURN BECAUSE OF EXCESS PLANE CHANGE.

> 3. If not recovered by then, the probe will remain on the current orbit for
> a month or two.
IT WILL, OF COURSE, DROP LOWER AND LOWER IN THAT PERIOD, AND WILL NOT REMAIN AT ANY ALTITUDE.

> 4. Currently, the probe is stable relative to the sun; it functions
> nominally, which means the onboard computing is not dead.
SEE QUIBBLE OVER STATEMENT 1-A. POPOVKIN GAVE NO DATA ON WHICH THIS 'HOPE' IS BASED, NOR IS THERE ANY REPORT OF ANY RUSSIAN SPACE OPTICAL SURVEILLANCE SYSTEM OBTAINING A SINGLE TRACKING ARC ON THE PAYLOAD. FROM WHAT I'VE READ ABOUT NUREK-OKNO AND OTHERS, I AM NOT CONVINCED THEY EVEN HAVE THAT ANGULAR TRACKING RATE CAPABILITY. I HAVE NOT EVEN SEEN ANY VISUAL DAWN/DUSK OPPORTUNITIES LISTED FROM THE KNOWN SITES.

> Hence, theoretical chances however small to establish communication with the probe exist.
SUCH CHANCES NO DOUBT 'EXIST', ON THE SAME ORDER OF LIKELIHOOD
AS THE PROBE BEING HIT BY ORBITAL DEBRIS AND EXPLODING. WE CAN'T
ESTIMATE THOSE CHANCES INDEPENDENTLY [INFO IS SECRET] AND POPOVKIN'S SELF-SERVING SAY-SO ISN'T SUFFICIENT GROUNDS TO BELIEVE IT.

> If communication is established, the exact reasons of what happened will be
> known. And it will be possible to reprogram/reset the BKU.
BUT SINCE IT WILL NOT BE POSSIBLE TO RESET THE PARKING ORBIT PLANE, THIS CAPABILITY LOOKS USELESS REGARDING ANY RESCUE OF THE ORIGINAL INTERPLANETARY MISSION. UNLESS A RUSSIAN BALLISTICIAN CAN EXPLAIN HOW THEY PLAN TO REDESIGN THE ESCAPE ASYMPTOTE -- I'M LISTENING.

> 5. If the probe is to fall to Earth, there is no danger of contamination as
> the probe will explode on reentry.
IF ROSKOSMOS TRULY BELIEVED THIS, THEY WOULD DEORBIT THEIR END-OF-LIFE VEHICLES OVER RUSSIAN TERRITORY. SINCE MOSCOW HAS A LONG, LAMENTABLE TRACK RECORD OF FALSELY CLAIMING THERE WAS NO CONTAMINATION DANGER FROM VEHICLES SUCH AS KOSMOS-954 [CANADA, 1978] AND MARS-96 [BOLIVIA, 1996], STATEMENTS OF THIS NATURE LACK THE SLIGHTEST CREDIBILITY.

> The exact time of reentry can be predicted when the probe' orbit decays to
> 180km [112 MILES].
LIKE THE RUSSIAN SPACE TRACK EXPERTS PREDICTED THE RECENT
UARS AND ROSAT ENTRY TIMES SO ACCURATELY? DOES POPOVKIN
THINK THAT HIS TARGET AUDIENCE HAS AMNESIA, OR IS HE TOO
ACCUSTOMED FROM HIS LONG [AND HONORABLE] MILITARY CAREER
WHERE HE WAS ABLE TO DICTATE DOGMA TO HIS MILITARY UNDERLINGS,
NOT REALIZING THAT IN THE CIVILIAN WORLD, PEOPLE HE CAN'T DISCIPLINE MAY WANT MORE REASONS TO AGREE WITH HIS CLAIMS THAN HIS SAY-SO ALONE?

JimO · « **Reply #46 on:** 11/14/2011 08:09 pm »

A good discussion of the 'garble factor' of making official statements at a press conference while putting NOTHING on the official website, is here:

http://www.parabolicarc.com/2011/11/14/popovkin-finally-provides-update-on-phobos-grunt-flunks-math/#more-32047

iamlucky13 · « **Reply #47 on:** 11/14/2011 08:13 pm »

Quote from: MondoMor on 11/14/2011 07:05 pm

RussianSpaceWeb has some good information on the ground hardware used (so far) to attempt contact with P-G:

http://www.russianspaceweb.com/phobos_grunt_kik.html

It is not encouraging to read.

Ironically and perhaps shortsightedly, I'm slightly encouraged by Mr. Zak's latest update. It paints a picture of more trouble utilizing the ground stations than I think even most of us closely following the situation realized. It leaves open the possibility that perhaps the spacecraft is not being totally deaf and mute, but rather they're just not tracking accurately enough.

This is thin speculation on my part, of course.

JimO · « **Reply #48 on:** 11/14/2011 09:39 pm »

There have been cases where Soviet-era spacecraft went a long time without allowing ground command but then were recovered. The Soyuz test flight called 'Kosmos-613' went for weeks. Even the FGB, when launched, rejected ground commands for several orbits, while the Russians and Americans were whooping it up at the post-launch party, in the dark about how it was teetering on the brink of failure.

JimO · « **Reply #49 on:** 11/14/2011 09:58 pm »

Phobos-Grunt hazard level rises -- lawyers are getting involved!!

Phobos-Grunt: a legal analysis of potential liability and options for mitigation
by Michael Listner
Monday, November 14, 2011
http://www.thespacereview.com/article/1968/1

sdsds · « **Reply #50 on:** 11/15/2011 12:21 am »

Quote from: riney on 11/14/2011 07:57 pm

Assuming the Russians were to ask, are there any U.S. ground assets that could be made capable of contacting/commanding the spacecraft in the available time?

I am unaware of any public statement about this by a person who has sufficient knowledge of the Russian and U.S. systems which would be involved.

That said, because F-G communicates in the X-band, if there were a non-classified organization within the U.S. that would be involved, it would be the Deep Space Network which AIUI is operated by JPL. It isn't clear that anyone associated with DSN has yet taken on the task of evaluating what the F-G communications requirements might be.

Jorge · « **Reply #51 on:** 11/15/2011 01:17 am »

Quote from: JimO on 11/14/2011 11:21 am

Quote from: Comga on 11/14/2011 03:25 am
Does that put them ~154 deg out, about as close to opposite as can be, and making any pass very quick?

OK... Now somebody with competence in spherical trig can please take these two planes with this RAAN difference, and calculate their actual out-of-plane value -- the angle between their two planes, not just the angle between their two equator crossing longitudes. I've forgotten how to do it.

I forgot the spherical trig method as well, but by computing the unit angular momentum vectors from i and RAAN, then taking the dot product of those, I get 99 degrees.

Nickolai · « **Reply #52 on:** 11/15/2011 01:50 am »

Not sure if this has been covered yet, but http://ria.ru/science/20111114/488421626.html states in the 5th paragraph:

Он также рассказал, что специалисты ведомства пытаются, в частности, провести ускорение поворотных механизмов аппарата. Кроме того, станция должна была начать работать, когда она была бы в нескольких десятках тысячах километрах от Земли и мощность передатчиков была настроена так, чтобы сигнал доходил туда, уточнил Поповкин. По его словам, эксперты опасались, что на близком расстоянии сожгут этим чересчур сильным сигналом аппаратуру зонда.

Popovkin further explained, that specialists are trying, among other things, to speed up the turning mechanisms at listening stations [the paragraph before stated that communications difficulties stemmed from tracking equipment being designed for deep space comms, not LEO]. Besides that, the spacecraft was supposed to start work [start transmitting?] when it was several tens of thousands of kilometers away from the Earth and the strength of the transmitters we set such that the signal would get there, Popovkin pointed out. As he says, experts have explained that at this close distance the will burn this for sure with a strong signal to the craft.

So it sounds like they haven't tried transmitting at higher power levels yet.

simplex · « **Reply #53 on:** 11/15/2011 02:18 am »

Maybe, Fobos-Grunt craft can still be used as a (quite expensive!) test platform for a successful Fobos-Grunt II even if no part of the spaceship will go further than a low - medium Earth orbit.

I do not think that Fobos-Grunt does not have an emergency command for releasing the Chinese satellite and splitting the spacecraft in three: the cruise stage, Chinese satellite and Phobos lander.

- Fuel tanks will be lost and crash on Earth.
- The Chinese satellite, once liberated, will be able to rise its orbit and become an Earth satellite and be tested thoroughly in the next year.
- Phobos Lander will also become an Earth satellite. Maybe they will attempt to make it approach a big known space junk.
- The Mars - Earth return module could also be released from the Lander through an emergency command and become an Earth satellite.
- Finally the reentry capsule will detach from the return module, at an favorable moment, and land as scheduled in Kazakhstan.

If the above sequence of events goes well then a Fobos-Grunt II craft can be built quickly and be ready for the 2013 Mars window with much more chances of success than Fobos-Grunt I.

Jason1701 · « **Reply #54 on:** 11/15/2011 02:23 am »

Quote from: simplex on 11/15/2011 02:18 am

Maybe, Fobos-Grunt craft can still be used as a (quite expensive!) test platform for a successful Fobos-Grunt II even if no part of the spaceship will go further than a low - medium Earth orbit.

I do not think that Fobos-Grunt does not have an emergency command for releasing the Chinese satellite and splitting the spacecraft in three: the cruise stage, Chinese satellite and Phobos lander.

- Fuel tanks will be lost and crash on Earth.
- The Chinese satellite, once liberated, will be able to rise its orbit and become an Earth satellite and be tested thoroughly in the next year.
- Phobos Lander will also become an Earth satellite. Maybe they will attempt to make it approach a big known space junk.
- The Mars - Earth return module could also be released from the Lander through an emergency command and become an Earth satellite.
- Finally the reentry capsule will detach from the return module, at an favorable moment, and land as scheduled in Kazakhstan.

If the above sequence of events goes well then a Fobos-Grunt II craft can be built quickly and be ready for the 2013 Mars window with much more chances of success than Fobos-Grunt I.

None of that can happen if they never make contact with the spacecraft, which seems by far the likeliest outcome.

simplex · « **Reply #55 on:** 11/15/2011 02:34 am »

They are trying to start the first stage (the ring) and then the cruise stage (the spheres). It is not clear that they are unable to split the craft in three and release the Chinese satellite. They should be able to do so.
For the moment they are not interested in such a stunt because it would mean that the mission had failed.

Jim · « **Reply #56 on:** 11/15/2011 02:41 am »

Quote from: simplex on 11/15/2011 02:34 am

They are trying to start the first stage (the ring) and then the cruise stage (the spheres). It is not clear that they are unable to split the craft in three and release the Chinese satellite. They should be able to do so.
For the moment they are not interested in such a stunt because it would mean that the mission had failed.

No, they can't even contact the vehicle, much less trying to start it. Since they can't contact it, they can't command it to split.

hop · « **Reply #57 on:** 11/15/2011 02:42 am »

Quote from: simplex on 11/15/2011 02:34 am

They are trying to start the first stage (the ring) and then the cruise stage (the spheres). It is not clear that they are unable to split the craft in three and release the Chinese satellite.

They are unable to contact the spacecraft in any way. No telemetry, no response to any commands.

Quote

They should be able to do so.

What makes you think that ? Normally, this would only be done after they reach Mars, and that would be done by an on-board command sequence, not directly commanded from earth. There's no reason to have it externally commandable.

simplex · « **Reply #58 on:** 11/15/2011 03:05 am »

Honestly, I do not believe the story according to which they are not able to send any command to the spacecraft.
They say, or better suggest, that no uplink has been possible just to get rid of a lot of questions from journalists.
Such a big spacecraft has multiple communication systems, high gain and low gain omnidirectional antenna. Something is wrong with the spacecraft but they have some bidirectional communication.
The Mars rovers have at least three antenna, three communication systems, each and the rovers are much smaller.

Eraser · « **Reply #59 on:** 11/15/2011 03:07 am »

I now have very little confidence in any official statements, because the upcoming parliamentary elections. Phobos-Grunt simply can not be considered as lost before the election.