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tedstryk
In Astronomy's February issue, they report that Russia has approved funding for the Phobos-Grunt mission. Design work has gone on since 1997, and the new design is scaled down to fly an a Soyuz rocket instead of the larger Proton. The main purpose is similar to Phobos-2, with the addition of a sample return. Also being discussed is the possibility of it carrying a few "meteorological stations" fof Mars itself. Generally, I have written this mission off as "never going to happen," but with the new Russian alliance with ESA, I wonder if they might be able to actually fly this thing. Also, with Putin's increasingly Soviet-style leadership, and with the likelyhood of lunar missions from China and India, Russian pride might drive this mission. If so, I have a concern. This mission sounds really, really ambitious. And the Russians have never even sent a fully successful Mars orbiter, and that is when they launched them in pairs or triplets. Still, if the mission flies, even if it doesn't bring back Phobos soil it might obtain some interesting results. Here is ESA's Phobos-Grunt page:
http://www.esa.int/SPECIALS/ESA_Permanent_...IJFW4QWD_0.html

Also, ESA has another page on potential Russian programs, although this seem to be nothing but pipe dreams at the moment. Would be a cool mission though.

http://www.esa.int/SPECIALS/ESA_Permanent_...0LFW4QWD_0.html

And also a page on the only partially realized current Russian project, its program to put instruments on other's spacecraft, such as HEND on Odyssey.

http://www.esa.int/SPECIALS/ESA_Permanent_...HMFW4QWD_0.html
SFJCody
There's a pdf document on these speculative missions here:


RussianProgram
tedstryk
That is some pretty interesting stuff. Back in the 80's, when our planetary program (other than already flying projects like Viking, Voyager, PVO, and ICE) wasn't flying any new spacecraft, the Soviets were the only major game in town. They spent the early part of the decade studying Venus (including the landers and the balloons), contributed a major component of the Halley flotilla, and then went to Mars with the Phobos mission. The Phobos spacecraft were the first of a new plan for exploration that included missions very similar to the Fortuna mission in that literature. They included balloons, rovers, and orbiters for Mars, and, yes, Phobos-Grunt (a much more sophisticated version). There was also an advanced Venera program. There was a great article sometime in 1988 in Astronomy about it. Then, of course, after the first of these new missions launched (Phobos '88), the whole Soviet system crumbled. Mars '96 (Which would have been Mars '90 - the original Mars'96 plan was a veritable Battlestar Galactica with rovers, balloons, and landers) managed to peter along and make it to the launchpad but was unlucky enough to have a bad upper stage on its launch vehicle. Phobos-Grunt, scaled down to fly on a Soyuz instead of a larger Proton rocket, was the only mission for which real design work continued. They have periodically presented other missions, both on their websites and at conferences, such as Venera-D and various asteroid missions, but I think they are generally sales-pitches in hopes of international funding which would be needed to fly them. Phobos-Grunt is the only mission that the Russian parliament and Putin have actually agreed to fund. That is why I take it more seriously. Putin feels threatened by Bush's Moon-Mars plan, and a Phobos sample return mission in 2009 would be a great way to upstage MSL. Of course, one has to hope that Russian space technology has improved...This mission will have to be longer lived than previous Russian spacecraft. But it has great potential.
AlexBlackwell
An interesting tidbit from Tony Reichhardt's News article in the December 15, 2005, issue of Nature:

"Russia's long-suffering space scientists had reason to celebrate last week as a generous funding increase was approved for the national space agency, giving hope to missions that have long been on hold.

[...]

"One such mission, called Phobos-Grunt, now seems to be on track to launch in 2009. It will head for the martian moon Phobos, where it will land and collect a soil sample before returning to Earth. The mission has been scaled down it will use conventional propulsion and launch on a Soyuz rocket, instead of the more expensive Proton but it should still manage to land 45 kilograms of scientific instrumentation on Phobos.

"Spacecraft engineers at the Moscow-based Lavochkin Association are laying plans for an ambitious mission called Luna-Glob, which would deliver an orbiter and a network of instruments to the Moon for geophysical studies. This mission would probably get funding only after Phobos-Grunt is well under way, says [Mikhail] Marov [of the Keldysh Institute of Applied Mathematics in Moscow]."

References:

Budget boost gets Russia back in the space game
Tony Reichhardt
Nature 438, 896 (2005)
doi:10.1038/438896b
Full Text

==================

At the risk of sounding curmudgeonly, I'll only say that I'll believe in this mission when I see it. I was at an International Astronautical Congress in Toulouse, France, a few years back when a presentation for this mission was given by individuals from the Moscow Aviation Insititute and the Lavochkin Association. None of the others present who heard the presentation believed it would ever happen, at least not without involvement from the U.S. or Europe. In fact, a few "western space professionals" laughed outright, and one said "they're [the Russians] just looking for outside support."

Having said that, I hope it does come off, given that the Aladdin concept never made the downselect in a couple of Discovery solicitations, and especially if Gulliver never gets selected as a future Discovery mission. Indeed, I think both Phobos and Deimos get short changed in the U.S. and European Mars exploration architectures.
ljk4-1
QUOTE (AlexBlackwell @ Dec 14 2005, 02:07 PM)
Having said that, I hope it does come off, given that the Aladdin concept never made the downselect in a couple of Discovery solicitations, and especially if Gulliver never gets selected as a future Discovery mission.  Indeed, I think both Phobos and Deimos get short changed in the U.S. and European Mars exploration architectures.
*


Ah, Gulliver! The name of a relatively simple lander planned for Mars back in the 1960s that would have shot out sticky strings to pull in some surface samples for analysis.

http://www.spacedaily.com/news/mars-life-03l.html

Question: Going on what we know about the Martian surface now and remembering the data from Viking, had Gulliver happened, would the scientists have concluded at the time that they did indeed find life on Mars?
ElkGroveDan
Let's hope they keep away from the Lipovitan-D.
AlexBlackwell
QUOTE (ElkGroveDan @ Dec 14 2005, 07:37 PM)
Let's hope they keep away from the Lipovitan-D.
*

Or its variant - "Lilliputian-D" tongue.gif
Decepticon
I say they rename the probe Mars-Lipovitan-D04A
Bob Shaw
QUOTE (ljk4-1 @ Dec 14 2005, 08:31 PM)
Ah, Gulliver!  The name of a relatively simple lander planned for Mars back in the 1960s that would have shot out sticky strings to pull in some surface samples for analysis.

http://www.spacedaily.com/news/mars-life-03l.html

Question:  Going on what we know about the Martian surface now and remembering the data from Viking, had Gulliver happened, would the scientists have concluded at the time that they did indeed find life on Mars?
*



From what I can tell, Gulliver was slated to be one of the Advanced Mariner experiments - certainly, the illustration in Gatland's 'Unmanned Spaceflight' appears to be of the Philco Lander. And I doubt it'd have coped well in the search for life!

Bobn Shaw
BruceMoomaw
The life detector on Gulliver was none other than Gilbert Levin's instrument -- so, had they flown that alone, there would certainly have been a tidal wave of "Life Found on Mars!" headlines that might have proven just a teensy bit premature.
Toma B
QUOTE (AlexBlackwell @ Dec 14 2005, 10:07 PM)
.......At the risk of sounding curmudgeonly, I'll only say that I'll believe in this mission when I see it.......
*

So it will be a scaled down version of "Phobos"...
Click to view attachment
I can still remember high expectations of that spacecraft...Mars orbiter, Phobos landing etc...
In the end; Phobos-1 was lost before it even reached Mars and Phobos-2 took "staggering amount of information including 38 images"...same basic design was again used on Mars-96 but it never had a chance to see Mars....
Russia (CCCP) has yet to score first successful mission to Mars...
As said above I'll believe it when I see it...
Wish them good luck anyway.
Richard Trigaux
I think that if the Russians are coming to an end of their economic difficulties and come back on stage for space exploration, everybody should be happy.
tedstryk
QUOTE (Richard Trigaux @ Dec 15 2005, 09:45 AM)
I think that if the Russians are coming to an end of their economic difficulties and come back on stage for space exploration, everybody should be happy.
*


I hope so. In the past, budgeted money has not been delivered...I hope hthey go through with this. It is a shame Phobos 2 did not return more images. One thing forgotten is that its main transmitter failed before arrival, so kind of like Galileo (though not as severe, Phobos-2 couldn't use compression like Galileo), Phobos 2 had great difficulty returning large data products.
ljk4-1
QUOTE (Toma B @ Dec 15 2005, 02:21 AM)
So it will be a scaled down version of "Phobos"...
Click to view attachment
I can still remember high expectations of that spacecraft...Mars orbiter, Phobos landing etc...
In the end; Phobos-1 was lost before it even reached Mars and Phobos-2 took "staggering amount of information including 38 images"...same basic design was again used on Mars-96 but it never had a chance to see Mars....   
Russia (CCCP) has yet to score first successful mission to Mars...
As said above I'll believe it when I see it...
Wish them good luck anyway.
*


While the Soviets never had a fully successful mission to Mars, they did have partial successes, and they did land the first spacecraft on the planet, even if they did all go bye-bye prematurely. Of course none of them returned nearly as much data and images as the US missions.
TheChemist
QUOTE (Richard Trigaux @ Dec 15 2005, 11:45 AM)
I think that if the Russians are coming to an end of their economic difficulties and come back on stage for space exploration, everybody should be happy.
*

Maybe when they 're done with their investments in the English premiership and F1, some money will be left for space exploration smile.gif
AlexBlackwell
QUOTE (ljk4-1 @ Dec 15 2005, 02:25 PM)
While the Soviets never had a fully successful mission to Mars, they did have partial successes, and they did land the first spacecraft on the planet, even if they did all go bye-bye prematurely.  Of course none of them returned nearly as much data and images as the US missions.
To put it mildly, I think that's an understatement. I certainly do not want to engage in bashing the Russians -- they have some fairly top notch scientists -- but their data return via spacecraft from Mars has been much worse than "[not] nearly as much...as the US missions." I would venture a guess, without having done a bit by bit comparison, that Mars Express alone has returned more data than all Soviet/Russian Mars missions combined.
AlexBlackwell
QUOTE (Richard Trigaux @ Dec 15 2005, 09:45 AM)
I think that if the Russians are coming to an end of their economic difficulties and come back on stage for space exploration, everybody should be happy.
I agree, and if/when I see hard evidence supporting this scenario, I promise to be happy. A notice in the press that some mission "seems to be on track to launch" four years from now doesn't get me too excited.
ljk4-1
QUOTE (AlexBlackwell @ Dec 15 2005, 12:03 PM)
To put it mildly, I think that's an understatement.  I certainly do not want to engage in bashing the Russians -- they have some fairly top notch scientists -- but their data return via spacecraft from Mars has been much worse than "[not] nearly as much...as the US missions."  I would venture a guess, without having done a bit by bit comparison, that Mars Express alone has returned more data than all Soviet/Russian Mars missions combined.
*


I may be wrong on this, but I remember reading that Soviet space philosophy when it came to robot deep space probes was to build them as best they could, but essentially "test" them in space. If they failed on the way, one simply pretended to the West that they never existed, learn from the mistakes if possible, and try to build a better one next time. The US view was build and test them to the max before sending them out.

This is one reason why the USSR had more launches and more failures than the US.
tedstryk
QUOTE (ljk4-1 @ Dec 15 2005, 08:14 PM)
I may be wrong on this, but I remember reading that Soviet space philosophy when it came to robot deep space probes was to build them as best they could, but essentially "test" them in space.  If they failed on the way, one simply pretended to the West that they never existed, learn from the mistakes if possible, and try to build a better one next time.  The US view was build and test them to the max before sending them out.

This is one reason why the USSR had more launches and more failures than the US.
*


That and the fact that the cover up was considered possible (even if in the end it wasn't. For example, the Mars 4-7 mission had serious computer problems, and the scientists wanted to delay, but the powers that be ordered that it go ahead, with the idea that if one of the landers managed to erp back a bit of data before its problems killled it, it would be the last chance to beat Viking. Mars-6 did return descent data, but it was very limited, and most know for an false reading from the pump for the mass spectrometer that made them think there was Argon in the atmosphere.
RNeuhaus
I think that previously Russian has failed many missions due mainly to political factors rather than technical reasons. The Soviet's leaders had made a lot of pressure and unrealistic judgment on engineers and scientists to do anything almost impossible, hurry up all things because there were a space race against the U.S. of America. to anywhere: Moon, Venus and Mars.

Then, now the view on the space is somewhat more calm than before so anybody are not in hurry to send any spacecraft to the space as a race but rather as on self pace rate in which it will guarantee a much higher mission success rate.

Hope that Russian, in that time, will manage better the space exploration programs without any kind race with any nation of Earth...rather better with more international cooperation

Rodolfo
JonClarke
QUOTE (ljk4-1 @ Dec 15 2005, 08:14 PM)
I may be wrong on this, but I remember reading that Soviet space philosophy when it came to robot deep space probes was to build them as best they could, but essentially "test" them in space.  If they failed on the way, one simply pretended to the West that they never existed, learn from the mistakes if possible, and try to build a better one next time.  The US view was build and test them to the max before sending them out.

This is one reason why the USSR had more launches and more failures than the US.
*



Don't know about the space environment test program but Moon, Mars and Venus landers were extensively tested on earth in extensive ground, drop and simulation chamber tests. It seems to have paid off with the venus landers but to with mars. Don't know why.

And yes Alex, you are a curmudgeon. I think they will pull it off. They are getting serious budget increases at last. And I don't think comparing Phobos 2 to ME is fair given that the design of ME 15 years more advanced - better compared with mariner 9 which returned lower quality and less diverse data but at lot more of it. If you are not excited by an annoucement that this mission is on track for 4 years i assume you are equaly unexcited by ML, which is also supposed to be on track for a launch 4 years from now.

Toma B: - you will find that Phobos 2 collected a lot more data than 38 pictures. There are at least 300 publications I can identify on this mission. As a sample return mission, there is no way that it can be considered a scaled down Phobos 2, given that that was did not involve sample return.

Ted: while the amount was erroneous, the interpretation of the Mars 6 lander MS data did rightly alert people to the possibility that Mars has above terrestrial proportions of Ar.

That said, the mission does scare me at bit. Hayabusa has shown how difficult small body sample return can be. I would like to see the Russians get a few more runs on the Mars board with some simple missions before trying something this ambitious. A criticism of their prevous Mars missions would be that (unlike with their lunar and venus probes) they did not iron out bugs with repeat missions but sent a succession of every more complex probes.


Jon
AlexBlackwell
QUOTE (JonClarke @ Dec 16 2005, 12:30 AM)
And yes Alex, you are a curmudgeon.  I think they will pull it off.  They are getting serious budget increases at last.

I sure hope you're right, Jon. Me, I've seen too many Russian "sales pitches" to be excited at this early juncture. Indeed, I've seen too many NASA "virtual slide show" missions that never left the PowerPoint file, too, and NASA has a much better track record over the past 10-15 years than the Russians!

QUOTE (JonClarke @ Dec 16 2005, 12:30 AM)
And I don't think comparing Phobos 2 to ME is fair given that the design of ME 15 years more advanced - better compared with mariner 9 which returned lower quality and less diverse data but at lot more of it.  If you are not excited by an annoucement that this mission is on track for 4 years i assume you are equaly unexcited by ML, which is also supposed to be on track for a launch 4 years from now.

Now who's making the unfair comparisons, Jon? smile.gif

At least MSL (I presume that's the mission you're referring to by "ML") has solicited and selected instruments. I'll concede, however, that that's no guarantee MSL will fly.
edstrick
The soviets and the Russians after them have had a severe problem with reliabilty in initial flights of series of spacecraft on lunar and planetary missions. After a series of sucesses and partial sucesses with the series-1 lunar missions (Luna 1 through 3, not including launch failures), they had sustained failures with the series-2 lunar series, Luna 4 through 8; before Luna 9 landed, 10-12 orbited and 13 landed.

The series 3 lunar missions started with the failure of a sample return mission (Luna 15, during Apollo 11), then succeeded with Luna 16, 2 Lunokhod rovers, 2 heavy lunar orbiters (who's science return seemed to be minimal) and 2 more successful sample returns (and 2 sample return missions that were reputedly damaged during landing attempts in the rough highlands south of Mare Crisium. On the whole, pretty successful.

Similarly, the one block-1 planetary launch and all the early series-2 planetary launches failed until Venera 4 in 1967, 5 & 6 in 69 probed the atmosphere, and finally Venera 7 landed and had a partially successful mission in 1971 (Venera 8 one opposition later was a complete success) All the series-2 Mars missions failed, though one that was launched as an engineering test after it missed the launch window to mars, Zond-3, did a successful lunar flyby. All the series-3 lander missions to Mars were failures, though the Mars 3 orbiter was a success, and the Mars 5 orbiter was a success that failed prematurely.

After failing to send missions to compete with Vikings at Mars in 75, the series-3 missions to Venus succeeded brilliantly. Venera 11 and 12 failed to turn on landed science after highly successful atmosphere descents, but 13 and 14 were full successes, 15 and 16 were successful radar orbiters (one had some problems), and Vega 1 and 2 venus landers and balloons were successful, and the Halley flyby missions were largely successful, though the imaging quality at the comet was fairly miserable (it did provide essential pathfinding targeting for Giotto).

The series-4 missions (2 Phobos missions and poor Mars 96, which was launched-to-death) failed, but the Phobos 2 mission was a substantial scientific success as a Mars orbiter before it failed during the Phobos orbit rendezvous operations. Then their budget failed.
Toma B
QUOTE (JonClarke @ Dec 16 2005, 03:30 AM)
Toma B: - you will find that Phobos 2 collected a lot more data than 38 pictures.  There are at least 300 publications I can identify on this mission.  As a sample return mission, there is no way that it can be considered a scaled down Phobos 2, given that that was did not involve sample return.
*


I have said "In the end; Phobos-1 was lost before it even reached Mars and Phobos-2 took "staggering amount of information including 38 images"...same basic design was again used on Mars-96 but it never had a chance to see Mars...."
But it wasn't data it should have colected...it was Phobos explorer and it died before almost any Phobos science was done...right?
Anyway I wish them luck with new spacecraft, first one in 10 (or so ) years...
Richard Trigaux
QUOTE (RNeuhaus @ Dec 15 2005, 08:33 PM)
I think that previously Russian has failed many missions due mainly to political factors rather than technical reasons. The Soviet's leaders had made a lot of pressure and unrealistic judgment on engineers and scientists to do anything almost impossible, hurry up all things because there were a space race against the U.S. of America. to anywhere: Moon, Venus and Mars.

Then, now the view on the space is somewhat more calm than before so anybody are not in hurry to send any spacecraft to the space as a race but rather as on self pace rate in which it will guarantee a much higher mission success rate.

Hope that Russian, in that time, will manage better the space exploration programs without any kind race with any nation of Earth...rather better with more international cooperation

Rodolfo
*


I Agree with all this.
edstrick
Toma B: "....But it wasn't data it should have colected...it was Phobos explorer and it died before almost any Phobos science was done...right?...."

Wrong. The Phobos mission hopper and landers were entirely phobos dedicated, but the main mission was targeted toward both Mars and Phobos. The early part of the In-orbit phase of the mission was in an eccentric orbit doing Mars science that could not be done later (especially fields and particles science) that could not be done as well from the more circular pre-rendezvour or the nearly circular rendezvous orbit. The thermal infrared Thermoscan and Near infrared mapping spectrometer data in particular was to continue after operations at Phobos had terminated.
RNeuhaus
QUOTE (edstrick @ Dec 16 2005, 01:13 AM)
After failing to send missions to compete with Vikings at Mars in 75, the series-3 missions to Venus succeeded brilliantly.  Venera 11 and 12 failed to turn on landed science after highly successful atmosphere descents, but 13 and 14 were full successes, 15 and 16 were successful radar orbiters (one had some problems), and Vega 1 and 2 venus landers and balloons were successful, and the Halley flyby missions were largely successful, though the imaging quality at the comet was fairly miserable (it did provide essential pathfinding targeting for Giotto).

The series-4 missions (2 Phobos missions and poor Mars 96, which was launched-to-death) failed, but the Phobos 2 mission was a substantial scientific success as a Mars orbiter before it failed during the Phobos orbit rendezvous operations.  Then their budget failed.
*

It is evident that the Soviet space's technology seems to be better suited for hot environment such as for Venus than for the cold environment ones of Mars. I seems funny that Soviet's technology is better suited for hot environment and its technology was so heavy that landing to Mars makes a lot more trouble than to Venus.

I seems that the more Soviet has tried, the Venus case with 18 missions (approximately) smile.gif versus 8 missions to Mars (approximately). Long learning curve due to the Soviet leaders' pressure to accelerate the mission.

To land on Venus is easier than to Mars? Then to land on Phobos must be much easier than to Mars. As I was the witness of Hayabusa, the landing on Phobos needs a spaceship that travels very slow toward Phobos, slower than to Mars. The other obstacle, the Phobos shape is not symetrical and I am not sure if it rotates (slow or fast) or not. If it rotates, it would be even more difficult to land.

Rodolfo
tedstryk
"To land on Venus is easier than to Mars? Then to land on Phobos must be much easier than to Mars. "

Phobos is a whole other game...Venus is easier to land on than Mars in that you can exclusively use the atmosphere to break to a speed in which it is safe to land. That statement does not indicate that Venus is an easier place for a craft to operate - it is just the plunking it down that is simplified.
edstrick
Landing on Venus is "easy"... The US did it on the Zeroth try. Pioneer Venus multiprobe missions ended at impact. The large probe and one small probe went silent at impact, one small probe lasted about a second, and the third lasted some ?67? minutes before it FRIED. The small probes didn't drop their heat shields so their bottoms were kinda "armored".

The reason Mars is HARD to land on is the atmosphere. On the Moon, or Mercury (ignoring the large Delta-V velocity change to get there) all you need is throttlable rocket engines, doppler sensing radars to measure vertical and horizontal velocity and altitude, a not very smart computer, and landing legs. Terminal guidance helps in rough terrain.

On Venus, all you need is an atmosphere entry heat shield, and a parachute. If you want to still be transmitting when you land, a pressure-vessle and lots of insulation are recommended.

On Mars, you need everything you need at Venus to do atmosphere entry, and a double parachute system, supersonic drogue chute followed by a LARGE, probably supersonic main chute. That keeps you from making a small crater lined with shiny metal bits before you're well below the speed of sound.

But then, you have to switch over to an entirely separate, second landing system. Either you need a hard landing system like Pathfinder/MER, comparable to the Luna 9 and 13 systems on the Moon, or a Viking/MPL/Phoenix rocket-propulsion landing system comparable to Surveyor/Apollo/Luna-16-sample-return/Luna-17-Lunokhod. You can get by with dinky rockets or dinky fuel tanks at least, cause you are going hundreds of miles/hr when you light the engines, instead of thousands, but it's just as complicated as if there was no atmosphere.

To land on Mars is essentially twice as complicated as landing on Moon or Venus. It could be worse. Try landing on the top of Olympus Mons. You don't have time to deploy a chute. You'd have to do an atmosphere entry, slow down to something like Mach 2, and blow out plugs in the heat shield as you light engines, maybe while blowing off the backshield. Build the lander directly into the heatshield. Instead of 6 minutes of terror, you'd basically have 4. Yow!
BruceMoomaw
Exactly the same problem applies for a human-sized lander (30-100 metric tons) ANYWHERE on Mars -- because a lander 64 times more massive than another of generally similar design will have only 16 times as much forward aeroshell area to brake it during entry.

This was the subject of Rob Manning's COMPLEX talk, which didn't make it into my final "Astronomy" article. No practical parachute design can be big enough to solve the problem; nor can high lift/drag aeroshells (like the "Ellipsled" proposed to aerocapture Neptune Orbiter, or even a winged vehicle) solve it.

The only possible solutions are (1) rocket engines capable of firing out the lander's bottom at supersonic speeds BEFORE it deploys its chute (as Ed suggests), or (2) a huge, 20-30 meter diameter decelerator capable of working at hypersonic speeds -- either rigid (in which case it must survive the heat of entry), or inflatable and deployed after the heating is over. Any of these three possible solutions, as you can imagine, will require a hell of a lot of new engineering work. Indeed, Manning says grimly: "These technologies are at very low TRL and have very uncertain outcomes on their success...We do not have high-likelihood Mars EDL systems to choose from." An advance test flight of any such general design will be necessary, with a lander weighing 10% as much as the actual manned lander. Yet another serious problem for those more eager than I am to see Footprints On Mars. Even the sample-return lander (about 1200 kg) will require a radically new parachute design.
ljk4-1
QUOTE (BruceMoomaw @ Dec 18 2005, 09:30 PM)
Exactly the same problem applies for a human-sized lander (30-100 metric tons) ANYWHERE on Mars -- because a lander 64 times more massive than another of generally similar design will have only 16 times as much forward aeroshell area to brake it during entry. 

This was the subject of Rob Manning's COMPLEX talk, which didn't make it into my final "Astronomy" article.  No practical parachute design can be big enough to solve the problem; nor can high lift/drag aeroshells (like the "Ellipsled" proposed to aerocapture Neptune Orbiter, or even a winged vehicle) solve it.

The only possible solutions are (1) rocket engines capable of firing out the lander's bottom at supersonic speeds BEFORE it deploys its chute (as Ed suggests), or (2) a huge, 20-30 meter diameter decelerator capable of working at hypersonic speeds -- either rigid (in which case it must survive the heat of entry), or inflatable and deployed after the heating is over.  Any of these three possible solutions, as you can imagine, will require a hell of a lot of new engineering work.  Indeed, Manning says grimly: "These technologies are at very low TRL and have very uncertain outcomes on their success...We do not have high-likelihood Mars EDL systems to choose from."  An advance test flight of any such general design will be necessary, with a lander weighing 10% as much as the actual manned lander.  Yet another serious problem for those more eager than I am to see Footprints On Mars.  Even the sample-return lander (about 1200 kg) will require a radically new parachute design.
*


Another problem to consider when landing on Mars with retrorockets: The fine powdery surface grains would spread far and wide and sandblast anything nearby. Better have landing pads far from the base, unless they come in on an airplane.

http://www.news.cornell.edu/Chronicle/05/1...e_research.html

How much surface dirt did the Vikings kick out when they landed? Considering how much they wanted to find microbes at the landing site, and they could not move around, I am surprised in some ways that they did not think of another landing method to disturb the ground as little as possible.
JonClarke
QUOTE (ljk4-1 @ Dec 19 2005, 02:38 AM)
How much surface dirt did the Vikings kick out when they landed?  Considering how much they wanted to find microbes at the landing site, and they could not move around, I am surprised in some ways that they did not think of another landing method to disturb the ground as little as possible.
*


Not Much wink.gif Viking had three landing engines with 18 nozzles fueled by specially purified hydrazine monopropellant. The hydrazine would not contaminate the ground and the 18 nozzles were specifically designed to minimise erosion on the ground. Some effects were noted though not particularly severe.

Jon
JonClarke
QUOTE (BruceMoomaw @ Dec 19 2005, 02:30 AM)
This was the subject of Rob Manning's COMPLEX talk, which didn't make it into my final "Astronomy" article.  No practical parachute design can be big enough to solve the problem; nor can high lift/drag aeroshells (like the "Ellipsled" proposed to aerocapture Neptune Orbiter, or even a winged vehicle) solve it.
*


Do you haver a link to his COMPLEX work - abstracts, reports, etc?

Jon
BruceMoomaw
Unfortunately, no -- at least for this document. I can keep looking for other documents with different names on ths subject, though -- or, failing that, at least type in the print in his PowerPoint presentation as an attachment here later on.

As for the Vikings: they shut off their engines at 3 meters altitude (versus 4 for the lunar Surveyors) -- and, as you say, they deliberately used a design of clustered small nozzles to minimize ground disturbance.
edstrick
Note regarding the Viking clustered engines: During testing of candidate engines -- maybe they already knew - that above a very few millibar pressures, a conventional bell-shaped engine nozzle's plume collapsed from a nearly hemisphereical plume to a focussed jet, as the plume detached from the nozzle. Simulated Viking landings in vaccuum chambers dug serious pits in the dirt and scattered it all over everywhere and everything. The Surveyor and Apollo LM engines would have done the same if Moon had a Mars like atmosphere.

Of course, the idiots we know who claim we never went to the moon don't know this. It's one of their stupid fallacies, that the rocket engines should have dug deep craters under the LM.
JonClarke
I was under the impression that Viking shut down just above the surface. "On Mars" however says that it occurred when the pads touched the ground.

Jon
BruceMoomaw
I may have to scrounge for confirmation, but I'm absolutely sure from what I read at the time that the engines shut off at 10 feet up. They were, after all, extremely concerned on that mission about the possibility of contaminating their surface samples with terrestrial organics.
RNeuhaus
I don't think that the next manned mission to Mars would be a spaceship bigger than the Moon Landing because of the already discussed reasons (low Martian density, not-uninform density atmosphere, high delta velocity (5-6 k/s).

The most practical design would be multiples spaceship, one for manned, the other for cargo (oxigen, food and water) and the other for return. This is only valid for the present time technology and let us see how the technology will improve within 20 years. smile.gif

About landing Phobos, it has other kind of challenges. Since it is orbiting from west to east 3 times a day (every 8:08 hour approx.) at 9,350 km from Mars and its is synchronous orbit radius to Mars. The spaceship would have to make many aerobraking orbits around Mars and have a much bigger fuel tanks in order to reduce its velocity before landing on the regolith covered by half meter of dust surface. Perhaps, it might have some ice as a water supplies to spaceship. Luckly it has no axis-rotation so the logistics for landing would not so complicated as to land to Eros or Itokawa.

Rodolfo
AlexBlackwell
Note that Zakharov et al. have an abstract to be presented at the upcoming EGU General Assembly 2006.
Bricktop
Video of Phobos-Grunt

mms://restart.roscosmos.ru/Media/FOBOS2.wmv
GravityWaves
Soyuz is soon launching from Europe's Kourou
mellow.gif
Their arianespace PDF files are online,
but it seems to a big download hundreds and hundreds of pages
AlexBlackwell
Does anyone have any objections to merging this thread with the "Phobos-Grunt a reality?" thread?
AlexBlackwell
I hope no one objects. I went ahead and merged the two topics.
Decepticon
I can't believe how many burns this probe needs to make!

I don't know about this one folks.

I have to admit Russian probes look cool. cool.gif
PhilHorzempa
[size=2]


Recent news seems to indicate that Russia will be increasing its spending
on space in the next few years. Does anyone in the UMSF community know
if the Phobos-Grunt probe is set for a definite launch in 2009? I would think
that with the successful sample return of Stardust, that the Russians may be
more inclined to actually fly this mission. Does anyone know if a delay to
a launch in 2011 is being discussed? Also, is this probe definitely set to be
launched on the Soyuz-Fregat, or is the Proton still a contender?
PhilHorzempa



The Russians have recently issued a video summary of the Phobos-Grunt
mission.

You can find it at this site.

http://restart.roscosms.ru/Media/FOBOS2.wmv


It sounds as if the proper way to pronounce the name of this spacecraft
is Phobos-Groond. Also, if anyone is fluent in Russian, a translation would
be welcome.

The Phobos-Grunt mission appears to be ambitious and exciting. Note that
the return capsule foregoes a parachute, and uses "lithobraking" upon
landing on the Earth!
Also, the return sample core appears to build on the technology of the
latter Luna sample return missions, with the core being coiled-up inside of
the return capsule.

One interesting observation concerns the animation of Phobos itself.
Those of us who know the features of our Moon well, will recognize the map
of our Moon's Far Side wrapped around an irregularly-shaped object.


Another Phil
ljk4-1
This very recent article (in Russian) contains a diagram of the Phobos-Grunt mission:

http://www.federalspace.ru/NewsDoSele.asp?NEWSID=1581
DonPMitchell
Here are NPO Lavochkin's pages about it: Fobos-Grunt
RNeuhaus
The Phobos-Grunt spacecraft has a typical Russian design: rustic and simple in order to save useful weigh. That spaceship has a much greater volume proportion for fuel to the rest than any sonda that I have ever seen. The reason is to bring fuel for two ways!

Rodolfo
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