Author Topic: LIVE: Zenit-2SB launch with Phobos-Grunt - November 8, 2011 (Read 663638 times)

Svetoslav · « **Reply #420 on:** 11/09/2011 01:41 am »

ANOTHER OFFICIAL INFORMATION:

According to Popovkin it's possible that the spacecraft wasn't able to reorient itself from the Sun to the Stars...

It is possible that the MDU never received commands from the sensors to start burns

Popovkin says - it's abnormal situation, but it was worked out during development of the project... and it's also known what to do in such situations

They will try reprogramming the spacecraft... No tanks were thrown out... No fuel was spent.

Svetoslav · « **Reply #421 on:** 11/09/2011 01:44 am »

Full Google translate link:

http://translate.google.com/translate?hl=en&sl=ru&tl=en&u=http%3A%2F%2Fria.ru%2Fscience%2F20111109%2F484401134.html

Svetoslav · « **Reply #422 on:** 11/09/2011 01:54 am »

http://www.interfax.ru/society/news.asp?id=215883

INTERFAX: Russian specialists have only three days to upload the new software before the batteries run out of power...

Popovkin: I won't say that the launch was a failure. It was an abnormal situation - but it has already been worked out.

Chris Bergin · « **Reply #423 on:** 11/09/2011 01:58 am »

Ok, a bit of hope at least!

Rocket Science · « **Reply #424 on:** 11/09/2011 01:58 am »

Quote from: Svetoslav on 11/09/2011 01:54 am

http://www.interfax.ru/society/news.asp?id=215883

INTERFAX: Russian specialists have only three days to upload the new software before the batteries run out of power...

Popovkin: I won't say that the launch was a failure. It was an abnormal situation - but it has already been worked out.

Thank you, it gives us some time then.

Robert

Skylab · « **Reply #425 on:** 11/09/2011 01:59 am »

Quote from: Svetoslav on 11/09/2011 01:54 am

INTERFAX: Russian specialists have only three days to upload the new software before the batteries run out of power...

Thanks again, Svetoslav! This reads like confirmation of a sensor/orientation issue.

JimO · « **Reply #426 on:** 11/09/2011 02:21 am »

They seem to have a stable vehicle and time to work it out. What they probably don't have enough of, because of the deterioration of the Soviet-era space tracking capabilities [no tracking ships, no TDRSS, loss of some western and southern in-country sites], is enough contact time -- 'AOS'.

Still, this could yet be pulled back from the jaws of defeat.

Eyewitness accounts from South America, and the ISS, might provide critical clues. It was prudent to ask for them, and it is extremely valuable that Western volunteer groups responded so energetically.

Svetoslav · « **Reply #427 on:** 11/09/2011 02:21 am »

http://ria.ru/science/20111109/484413896.html

Unfortunately I bear once again some bad news...

Specialists are already working on two versions about why the spacecraft wasn't able to switch to Star orientation.

The first one is a programming mistake. If this is true - it can be corrected easily and the spacecraft will fly to Mars.

The second version - a hardware problem - failure of hardware components - like sensors... This would mean that Phobos-Grunt can't continue its trek to Mars.

Ronsmytheiii · « **Reply #428 on:** 11/09/2011 02:23 am »

Quote from: Svetoslav on 11/09/2011 02:21 am

The first one is a programming mistake. If this is true - it can be corrected easily and the spacecraft will fly to Mars.

You know what that means.....

JimO · « **Reply #429 on:** 11/09/2011 02:36 am »

We need visual passes for the vehicle for the next 24 hours, so observers can search for any nearby objects to help characterize the vehicle's status. It's in a low, fast orbit and these passes will be challenging.

Chris Bergin · « **Reply #430 on:** 11/09/2011 02:43 am »

Given we don't have much official info to play with, I've provided a short summary of the state of play into Williams's main article:

http://www.nasaspaceflight.com/2011/11/live-zenit-2launch-fobos-grunt-sample-return-mission-to-phobos/

Excellent thread, with lots of very good contributions - and my earlier extended comment is no longer valid as I misunderstood what the person on twitter was aiming at. So that's all good now

.

mr. mark · « **Reply #431 on:** 11/09/2011 02:49 am »

Gees... I leave for a couple hours and all heck breaks loose on the spacecraft. Well, it's looks like I'm going to have to back read a bunch of pages. Sounds serious though, I hope flight controllers can work the problem.

joek · « **Reply #432 on:** 11/09/2011 03:10 am »

Agree great article and great thread. While I'm anxious for updates, I empathize with the mission crew and the pressure they must be feeling, let them do their jobs, and restrain myself and patiently await further word.

Nickolai · « **Reply #433 on:** 11/09/2011 03:52 am »

Not sure if this is the best place to bring it up but I'm a little confused by the article, specifically the translation. Fobos is not the name of the martian moon, it's Phobos. The Russian letter "ф" is pronounced similarly to "f," but we're not talking about some place called Fobos, we're talking about the Martian moon Phobos. A nitpicky point perhaps but I disagree that Roscosmos has been mistranslating the name of the mission.

Also, according to the Space Review (http://thespacereview.com/article/1966/1) Phobos-Grunt "is the heaviest solar system explorer ever (more than twice the second-heaviest, Cassini).", not just the heaviest built in the former USSR.

JimO · « **Reply #434 on:** 11/09/2011 04:24 am »

Quote from: Svetoslav on 11/09/2011 01:54 am

http://www.interfax.ru/society/news.asp?id=215883

INTERFAX: Russian specialists have only three days to upload the new software before the batteries run out of power...

As I understand it, the solar panels do not unfold until AFTER the completion of the burns. But while folded, do they generate ANY 'trickle power'?

Another time constraint is the rate with which the probe's parking orbit is precessing -- about 6-7 degrees per day -- out of the optimal plane for insertion onto the trans-Mars trajectory. Each day means the need for a bigger burn to correct for the growing planar error.

JimO · « **Reply #435 on:** 11/09/2011 04:28 am »

Quote from: ntrgc89 on 11/09/2011 03:52 am

.... according to the Space Review (http://thespacereview.com/article/1966/1) Phobos-Grunt "is the heaviest solar system explorer ever (more than twice the second-heaviest, Cassini).", not just the heaviest built in the former USSR.

I don't accept that claim, since the probe's mass is presented in LEO parking orbit, prior to insertion on the trans-Mars route. More than half of that mass disappears by the time it's on interplanetary cruise.

But the mass IS a critical issue, BECAUSE it's now of the heaviest satellites that might randomly fall back to Earth. If a controlled de-orbit can't be accomplished, we're talking about a spacecraft reentry within a week or two far more hazardous than the recent high-fear-factor falls of UARS and others, aren't we?

slavnus · « **Reply #436 on:** 11/09/2011 05:14 am »

prelaunch report from Baikonur

Everybody fingers crossed!!!

JimO · « **Reply #437 on:** 11/09/2011 05:25 am »

Apparently there's a few grams of radioactive cobalt-57 in one of the soil analysis instruments. Doesn't look like any significant contamination threat if/when it falls back to Earth.
http://vz.ru/news/2011/11/9/537080.print.html
http://www.ria.ru/science/20111109/484486608.html

jcm · « **Reply #438 on:** 11/09/2011 05:34 am »

Quote from: ntrgc89 on 11/09/2011 03:52 am

Not sure if this is the best place to bring it up but I'm a little confused by the article, specifically the translation. Fobos is not the name of the martian moon, it's Phobos. The Russian letter "ф" is pronounced similarly to "f," but we're not talking about some place called Fobos, we're talking about the Martian moon Phobos. A nitpicky point perhaps but I disagree that Roscosmos has been mistranslating the name of the mission.

Also, according to the Space Review (http://thespacereview.com/article/1966/1) Phobos-Grunt "is the heaviest solar system explorer ever (more than twice the second-heaviest, Cassini).", not just the heaviest built in the former USSR.

There's a confusion here between translation and transliteration.
If you want to TRANSLATE the probe's name, you should say "Phobos-Ground" or "Phobos-Soil". And you should refer to the Union-TM spaceship docking with the Star module, not the Soyuz-TM docking with Zvezda, etc...
but in TRANSLITERATION, which we normally do for names, it is useful to have a fixed mapping between the two alphabets (in this case Cyrillic and Roman) - this helps because if a reader knows both they can more reliably guess what the original Cyrillic was. Mapping the Russian letter Ф to the English letter F, rather than Ph, is a common choice - either would do as long as you are consistent, but in most Western space historiography we've picked F.

It's a Russian space probe, so I prefer to render the Russian spelling as best
I can. Now when I talk about the moon of Mars, that isn't Russian, and there's
already an English name for it, so when TRANSLATING a Russian statement I talk about the Fobos-Grunt mission to the moon Phobos.

When rendering names from another language or alphabet it's always a tricky choice - is the notorious late terrorist called Osama bin Laden, Usama bin Laden, or (translating) Leonine Ladenson? Transliterating is usually a better choice than translating in my opinion.

Meanwhile... crossing my fingers that the team can save the mission, whatever its name is..

Moe Grills · « **Reply #439 on:** 11/09/2011 06:33 am »

Quote from: Svetoslav on 11/09/2011 02:21 am

http://ria.ru/science/20111109/484413896.html

Unfortunately I bear once again some bad news...

Specialists are already working on two versions about why the spacecraft wasn't able to switch to Star orientation.

The first one is a programming mistake. If this is true - it can be corrected easily and the spacecraft will fly to Mars.

The second version - a hardware problem - failure of hardware components - like sensors... This would mean that Phobos-Grunt can't continue its trek to Mars.

If it's a hardware problem like sensors, wouldn't there be some redundancy built in to the system? Perhaps four sensors, instead of three? So if one fails the other three are sufficient?

Or, if one set of propellant valves fail on the Freget, would there be a
redundant set or bypasses?

I think that old saying is true: Give engineers the time to work out a problem, and they will....I hope it is this time.
I don't share in Jame Oberg's pessimism.