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Unmanned Spaceflight.com > Mars & Missions > Past and Future
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tolis
The plot thickens..apparently there is a statement made at the bottom of page 1 of the same report:

www.russianspaceweb.com/phobos_grunt.html

to the effect that the presently baselined LV (ie the Zenit) *can* send P-G+Y-H to Mars in 2011!

mps
Maybe the Zenit was considered powerful enough at the time, but the s/c maxed out its mass budget?
tolis
That is quite likely. The majority of flight projects have a tendency to gain mass with time.
How much the actual flight model ends up weighing depends on a particular project's mass "discipline".
Paolo
Anatoly Zak has an update on F-G, it seems like the soil sampler would not work and its replacement with a drill was one of the reasons that caused the delay to 2011
http://www.russianspaceweb.com/phobos_grun...flight.html#gzu
this is funny because he has previously reported that the drill was discarded as it would not work in the weak gravity of Phobos...
Hungry4info
Have they found a way around that? Maybe a mechanism to push it into the soil?
Gsnorgathon
They'd pretty much have to harpoon Phobos in order to do that, wouldn't they? Or fire thrusters to hold the spacecraft against the surface. Otherwise, pushing the drill into the surface would just push the lander up.
Explorer1
Rosetta's lander Philae has just that; a harpoon to stick it to the surface of the comet. Whether such a thing would work on rock instead of ice remains to be seen, if Phobos-Grunt is even using that method.
Paolo
A short release in Russian on the site of the space agency Roskosmos
http://www.roscosmos.ru/main.php?id=2&nid=9603
In it, the new sampler is described as a "penetrator" and "a sort of pneumatic drill".I suspect it to be something resembling Beagle 2's "mole"
Paolo
Poland will apparently have a penetrator on Fobos-Grunt
http://press.cbk.waw.pl/10/cbk10040801/
I am not able to read Polish, but I have seen reports that it will be used to collect samples, which seems a bit strange to me...
centsworth_II
QUOTE (Paolo @ Apr 11 2010, 10:30 AM) *
Poland will apparently have a penetrator on Fobos-Grunt...

From this Google translation, it looks to me like this is a sort of remote sample collector that will not transmit reaction forces from its activity to the spacecraft and force it from the surface. I don't know how the penetrator works without forcing its own self from the surface. Google calls the penetrator a "hamster". I suppose that after the sample is collected, the "hamster" is retracted by a tether to the sample container.

"The key objectives of the mission should be to provide material samples to Earth from the surface of Phobos, satellite of Mars. The material will be downloaded through the Polish penetrator and placed in a container and the inside of Russian capsule....

....in the case of a device used for driving [into] the ground, [low gravity] becomes a serious obstacle.... the reaction....would result in rejection of the lander from the surface. Due to unique design, the Polish penetrator can hammer on [its] own....if the surface has proved to be too hard for other manipulators, designed for loose soil... [the] Penetrator will serve as the testing of thermal and thermal conductivity of the surface of Phobos."
Phil Stooke
Paolo, check your own post just above! It's a mole, not a hamster. It's not the kind of penetrator you drop from orbit, but it can still collect subsurface samples. The Beagle 2 analogy is a good one.

Phil
centsworth_II
QUOTE (Phil Stooke @ Apr 11 2010, 12:11 PM) *
Paolo, check your own post just above!
The Yahoo Babelfish translation of the article linked in that post calls the penetrator a "pick hammer". I wonder if that is a realistic description of its mode of operation:

"...new manipulator is the pick hammer, which makes it possible to separate the part of ground and to move [it] into the receiving device."
Paolo
A rough translation from a Polish contact of mine:

QUOTE
Polish Space Research Center in Warsaw started it's work on geological penetrator called CHOMIK, that will be used on Russian mission Phobos-Grunt. In few years time the sample of Phobos collected by penetrator will land back on Earth.

Main goal of the mission is to return sample of Phobos material from it's surface. Material will be collected by polish penetrator and then placed in special container which will be installed inside Russian return capsule. The capsule itself is supposed to land in 2014, Kazakhstan.

The agreement with Space Research Institute of Russian Academy of Sciences and Lavochkin was signed on April 2nd. Polish scientists will gain rights to send their representatives into team that will study the material taken from Phobos. Polish container for sample would be returned after extraction.

Thanks to it's unique construction Polish penetrator can dig itself in on it's own and only at the beginning of the procedure the lander mass is used to allow the sampler to go in. After fist few cycles the penetrator is anchored to the surface in a way that allows continuous operation without additional forces working on the lander.

CHOMIK guarantees successful sample taking in both soft and hard materials - too hard for other designs, more suited for loose material.

Penetrator will also be used for scientific data gathering - especially thermal studies of the ground.
rlorenz
QUOTE (Paolo @ Apr 11 2010, 10:30 AM) *
Poland will apparently have a penetrator on Fobos-Grunt
http://press.cbk.waw.pl/10/cbk10040801/
I am not able to read Polish, but I have seen reports that it will be used to collect samples, which seems a bit strange to me...


The Polish Space Research Center has developed a self-hammering drill (similar sort of principle to
the Beagle 2 mole) that is, used on the Rosetta lander Philae to insert a thermal properties
probe into the cometary surface. Here's a picture (inverted, the tall slender part is the thermal
probe, the hammer part is at the bottom) I took at the 2nd International Workshop on Penetrometry
in the Solar System in Graz, Austria in 2006 (IIRC the drill was demonstrated at the workshop)

Note that this system is quite separate from the
pyro-launched barbed anchoring harpoons that hold Philae down.

From the description I could readily believe that an adaptation of this device is being flown on P-G.
Paolo
QUOTE (Paolo @ Jan 3 2009, 02:29 PM) *
According to the IKI report, Italian participation also is in doubt, due to financing problems from our space agency


resuscitating this old post, the latest F-G payload in http://sci.esa.int/science-e/www/object/do...fobjectid=46877 does not include any Italian instrument. Too bad!
Phil Stooke
No sign of METNET, the Finnish lander, either.

Phil
ElkGroveDan
QUOTE (Phil Stooke @ May 3 2010, 04:19 PM) *
No sign of METNET, the Finnish lander

That's because it's not Finished yet, Phil.
nprev
Phil Stooke
Couldn't have put that better myself!

What is this place becoming? Punmannedspaceflight.com?

Phil
elakdawalla
That's it. Dan, Phil, time outs for both of you.
ilbasso
Wow, Doug has barely been out of the country a week, and the place has gone down the tubes.
Phil Stooke
Sorry!

Phil
Phil Stooke
On a more serious note...

Regarding the earlier Phobos missions (I didn't want to start a whole new thread for one question): Phobos 1 failed on its way to Mars. I'm trying to find anything I can on the expected Mars flyby date and distance, even though the spacecraft was not working. Can anyone help?

Phil
Paolo
QUOTE (Phil Stooke @ Jun 3 2010, 04:14 PM) *
I'm trying to find anything I can on the expected Mars flyby date and distance,


in Robotic Exploration of the Solar System - part 2 I have written the date as 23 January 1989, but I don't remember where that info came from. and I have no informations on the flyby distance
tolis
A rather comprehensive update on Phobos-Grunt may be found at

http://www.russianspaceweb.com/phobos_grunt_2010.html


Tolis.
Phil Stooke
Thanks for that. It's too bad that METNET can not be carried. On another note there's a very nice paper on landing site selection in Solar System Research, v. 44, no. 1, Feb. 2010, by Sasha Basilevsky and Tania Shingareva.

Phil
Paolo
A picture of what appears to be FG's ascent stage on the Novosti Kosmonavtiki forum

Phil Stooke
Yes, they're getting ready to transport it to Kazakhstan strapped on top of a Lada.

Phil
ugordan
LOL!
Paolo
QUOTE (Phil Stooke @ Jun 28 2010, 08:15 PM) *
Yes, they're getting ready to transport it to Kazakhstan strapped on top of a Lada.


and what is the bicycle in the right corner for?
jekbradbury
To tow the Lada!
ugordan
Now that's just silly. Everyone knows Lada is self-propelled.
charborob
QUOTE (Paolo @ Jun 28 2010, 01:29 PM) *
and what is the bicycle in the right corner for?

Spare parts?
Phil Stooke
Now people, could we please try to take this seriously?

Phil
Astro0
Article on the BBC website.
http://news.bbc.co.uk/2/hi/science_and_env...nt/10414237.stm
Drkskywxlt
Not trying to be negative here, but just realistic...I don't think this mission has a snowball's chance to accomplish all its goals. Shouldn't Russia try something a little less ambitious for it's first mission in 20 years than the longest sample return mission yet attempted? Perhaps an orbiter with a new instrument suite?

Honestly, I'll be amazed if this mission even gets into orbit.
ugordan
QUOTE (Drkskywxlt @ Jun 29 2010, 03:45 PM) *
Shouldn't Russia try something a little less ambitious for it's first mission in 20 years than the longest sample return mission yet attempted?

What are your thoughts on JAXA and Hayabusa?
Drkskywxlt
QUOTE (ugordan @ Jun 29 2010, 10:07 AM) *
What are your thoughts on JAXA and Hayabusa?


Hayabusa was a technology demonstration as a primary mission. JAXA knew it was a longshot to return samples. Also, JAXA has built up a broad, experienced talent base working on several planetary missions in the last 10-20 years. They have the engineering and scientific know-how well honed. Russia had that knowledge and, as shown in that BBC article, has lost it or it is pretty rusty. I think it's great that they want to start flying missions again, but I think they ought to start small. If Phobos-Grunt was a US mission, it would be New Frontiers class, most likely. Japan, China, and India have all started with (successful) but much smaller missions to get their feet off the ground.
djellison
They started small. 50 years ago.
Drkskywxlt
full inline quote removed - admin

Of course they did...and they had great success. Now they're starting over.
djellison
Like it or not - they're doing this. And 'I told you so' if it fails is really rather bad taste, because none of us is equipped with enough information about how well this mission has actually come together and how realistic and ambitious it actually is.

As discussions go, it's fairly rich in futility.
charborob
Coming back to the picture on post 327, surely this must be just a mock-up, not the real thing. I don't think they would transport the hardware like that without encasing it in some protective box or something.
hendric
In Soviet Russia, space probes put you in the box!

One would assume that they plan to put this into an oven or something for planetary protection purposes, right?
Drkskywxlt
QUOTE (djellison @ Jun 29 2010, 11:54 AM) *
Like it or not - they're doing this. And 'I told you so' if it fails is really rather bad taste, because none of us is equipped with enough information about how well this mission has actually come together and how realistic and ambitious it actually is.

As discussions go, it's fairly rich in futility.


I'm not trying to act haughty and set myself up for "I told you so". If this works, I think it'll be fantastic!

No, we don't have much information about this, but I think there's enough in the media and we all know enough about NASA/ESA spacecraft to make some comparisons. This is a very ambitious mission done on a budget that's most likely nowhere near what a comparable mission would budget in the US or Europe. That strains credibility and makes me doubt its success possibilities. I think if most people reading this look at it objectively, they'd come to the same conclusion as I. Again...I'm not wishing disaster or failure. I just wish they'd improve their odds by shooting at a lot lower target.
nprev
QUOTE (hendric @ Jun 29 2010, 10:22 AM) *
One would assume that they plan to put this into an oven or something for planetary protection purposes, right?


How does that work exactly in the case of Phobos-Grunt? Do they have to sterilize to Mars surface standards as a precaution against accidental impact, or to the (presumably much less stringent, if any) standards for asteroids & other small bodies, or just do the standard stuff (nothing?) for straight orbiters?

Hungry4info
@Drkskywxlt

I know what you mean... they haven't had a successful interplanetary mission in a long time.

I'll also be amazed if it makes it to orbit. But I'm sure going to be cheering for them all the way laugh.gif
Phil Stooke
Conditions are much better now than they were in the time of Mars 96. The amazing thing is that Russia managed to launch Mars 96 at all. People were working without pay, buildings weren't being heated - we could go on. The situation is greatly improved, so even if there are legitimate concerns there's no need to expect a total failure. I'm just writing up the section on Phobos 2 for my new book, and I hope to have a lot more to say about Phobos-Grunt than I had to say about Phobos 2.

Phil
Phil Stooke
And speaking of my book... here's a comparison of maps of Phobos made from five different missions. From top to bottom they are Mariner 9, Viking, Phobos 2, Mars Global Surveyor and Mars Express. The last one cheats a bit, it is largely Mars Express but areas seen better by other missions (mainly on the right, or trailing, side) are filled in with that data. I haven't looked to see if any areas are completely unseen by Mars Express yet.

Phil

Click to view attachment



The south pole bit on the Mars Global Surveyor map might come as a surprise to some folks. It is seen in Marsshine.
Phil Stooke
Can anybody help me with something...???? I wouldn't normally ask for something like this, but I'm running up against all sorts of problems getting a certain journal article in a readable form.

This is what I really need: Figure 2 of "Phobos sample return mission" (Galeev et al., 1996. Adv. Space Research, v. 17, no. 12, pp. 31-47).

Our library used to have this on paper, but now it's only available online. Fine - I have the file on my screen now. But the figure is illegible, a solid black mess.

So - if anyone has this on paper, or has an online version which is legible - just that figure - can you send me a message or email? I may need nothing more than a brief description of what it shows. In fact it might not show what I want, so the briefest comment might be enough.

Phil
Phil Stooke
Speaking of Phobos sample return, here's an illustration from my work in progress... sampling sites for the Aladdin mission, for both Phobos and Deimos. Deimos is the bottom map, Phobos the two upper ones. It's interesting to see that Phobos 2 was to land nearby (right end of middle map) and Phobos-Grunt is going to this same area as well - for dynamic and illumination reasons. If you land on the other side of Phobos, facing Mars, you lose illumination during the frequent eclipses as well as at night.

My Atlas of Mars Exploration is now all but finished (4 illustrations to go) in a first draft form. Another year to fix it up.

Phil

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