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Posted by: Marcel May 3 2005, 11:11 AM

Does anybody know when and how many MSL will go, or when the decision on this will be made ?

Posted by: djellison May 3 2005, 11:16 AM

Theisinger's said that a judgement call on Skycrane needs to be made by the end of this year - and I'd imagine the call how many, and when, will be made shortly thereafter

Doug

Posted by: Marcel May 3 2005, 11:30 AM

Ah, but how are they going to decide on the skycrane, when there's no new experimental data on the subject ? I suppose there are no tests scheduled before the end of the year.....

Posted by: djellison May 3 2005, 11:55 AM

There's some testing happening this year on the skycrane idea I believe - there was a swathe of documents in JPLs aquisition website for a rig to simulate skycrane ops (although to be honest it doesnt appear to simulate anything even slightly complex which couldnt be done quicker and cheaper in a virtual simulation)

Doug

Posted by: BruceMoomaw May 3 2005, 07:17 PM

They're definitely going to run the ground tests this summer -- and I regard them as necessary, given the number of subtle aspects of this gadget (twisting, whiplash in the lines, etc.) which would be hard to simulate precisely in a virtual simulation. (Remember that Mariner 10 was almost ruined by a resonant flexing of its magnetometer boom that kept making it do the hula uncontrollably -- and which wasn't picked up on the ground because it existed only in 0-G. That's how subtle material interactions can be in spacecraft dynamics.)

Posted by: Marcel May 4 2005, 06:48 AM

Why don't they use semi flexible booms, (say 3 or 4, to prevent twisting)extendable from the crane down, like telescopic fishing rods ? It will definately damp out unwanted movement of the rover with respect to the crane during the critical (final) stage before landing. I don't mean rigid, i don't mean rope like.....something in between.

Posted by: edstrick May 4 2005, 09:58 AM

Regarding the number of MSL missions that should fly.. they SHOULD fly 3. Build them at 2 year intervals. Fly #1 in '09, #2 in '11 and #3 in '13.

There is a precedence for this. Pioneer Jupiter missions were launched 13 months <1 jupiter launch window interval> apart.

If #1 blows it, like polar lander did, you can fix the booboo and fly #2. Engineernig tweeks and upgrades can be applied to #2 based on #1's early performance. #3 could have significantly upgraded or modified science payload. Each mission can be targetd based on science results of previous missions and orbital surveying done in the meantime.

Posted by: djellison May 4 2005, 11:33 AM

#3 is the only one that could derive engineering changes from #1.

You have 26 months from launch-to-launch

Call 8 months of that the cruise (sometimes more, sometimes less) - so you have 18 months.

The MER's spent about 6 months at KSC being checked out, bolted together and stock on a firework. - Giving you 12 months to define, design, build, test, rebuild, retest, integrate, and re-test at system level any changes you want - and then re-test at a system level to ensure your changes dont impinge on any other part of the spacecraft.

The only changes I could imagine being feasable are software or instruments.

Doug

Posted by: Marcel May 4 2005, 01:08 PM

And these changes can be important ones !

I agree though about the timeline and i still feel like i want to see 2 rovers leave in the same window. Make 2 other ones in the next window. Since the breathtaking succes of these two MER's, sending two should be the standard.

Not only because of the bigger chance of at least one succesfull mission,

not only because of the fact that you get the science of two locations if both succeed, but

also because if you start building these kind of machines, you might as well built another one (it's cheaper).

A dutch saying says: "on one leg you can't walk" (if someone asks you if you want a second beer). So yes, I want another one !!

Posted by: tedstryk May 4 2005, 01:36 PM

I would think that, using Skycrane, it is a good idea to sent one in 2009, and make sure it sends engineering data all the way down, so if something goes wrong, we have an idea what went wrong. Then, begin sending them two by two in 2011, taking in to account the results in 2009. Granted, if it were a severe problem it couldn't be fixed that quickly, but at least the 2011 MSLs would not have launched yet, so they could be fixed and sent in 2013. I think that unless a safer landing technique is found, this is the way to go.

Posted by: BruceMoomaw May 4 2005, 07:57 PM

[quote=Marcel,May 4 2005, 06:48 AM]
[[/quote]
Why don't they use semi flexible booms, (say 3 or 4, to prevent twisting)extendable from the crane down, like telescopic fishing rods ? It will definately damp out unwanted movement of the rover with respect to the crane during the critical (final) stage before landing. I don't mean rigid, i don't mean rope like.....something in between.

[/quote]
___________________________

No. That kind of semi-flexibility would be extremely difficult to program the descent rocket autopilot to compensate for, even after extensive ground testing. That, after all, is precisely how we got those self-reinforcing resonances in the Mariner 10 magnetometer boom, and the problem in this case would be far worse.

Now, I myself did seriously consider the possibility of a COMPLETELY rigid attachment between the rover and the descent stge, or at least as rigid as we could make it -- using either a pyramid of 3 or 4 cables fastened from the corners of the lander to the corners of the rover, or else a lightweight telescoping metal boom made out of a flat metal strip that curled its edges into a tube as soon as it was unrolled from the descent stage (a technique that's often used for spacecraft booms, including the sampling arm on the Vikings). I thought that this, by eliminating any swinging or twisting by the rover as it's being lowered, would simplify the problem -- but Nick Hoffman heaped scorn and wrath on my head, and then MSL engineer Pete Theisinger himself confirmed at the Mars Roadmap meeting that it causes more trouble than it solves. Such a rigid linkage makes the descent stage itself tilt back and forth, and apparently the control difficulties of cancelling this out with its descent engines are actually harder than having the descent stage keep itself hovering stable while lowering the rover on a loose cable (or, in reality, 3 cables fastened to corners of the rover but converging at a single point on the descent stage to allow swinging and twisting). Not being an engineer, I bow to their judgment -- apparently the only valid choices are a free-dangling Skycrane or no Skycrane at all.

Posted by: BruceMoomaw May 4 2005, 08:06 PM

They may actually do that -- but a far better scheme is, I think, to launch them at 4-year intervals. The main purpose for flying more than one MSL, as I've mentioned above, is to have each one look for trace organics at one place on Mars -- after which they'll send a sample return to the same place. If they launch just one MSL and it finds no organics, they'll be Up That Creek as to where to send the sample return mission -- and if MSL-1 finds no organics, they'll want to take some time to decide the best place to send MSL-2, instead of having to launch it to a predetermined landing site almost as soon as MSL-1 comes up empty-handed. (They may very well also want to modify MSL-2's instruments depending on MSL-1's results.) Ditto for MSL-3 if #2 also comes up empty. And with this wider gap between missions, you also have the ability to simply cancel the remaining MSLs without going to the expense of building them -- and move instead directly to the huge sample-return mission -- as soon as one MSL does find organics.

Posted by: BruceMoomaw May 4 2005, 08:09 PM

Footnote: I was told by an Inside Source yesterday that MSL-1 may well be launched in 2009 after all -- but he wasn't free to tell me his own reasons for thinking so. As I say, I rather hope they don't do it; the first Mars Telecom Orbiter should go up 2 years in advance -- and I think they should also launch the right kind of Mars Scout mission in 2009 instead (such as a methane-mapping orbiter).

Posted by: MaDeR May 12 2005, 09:35 PM

My 2 cents: If I have to choose between 2009 with 1 MSL and 2011 with 2 MSL, I choose 2011. Two year longer wait is worth it. Two big, heavy and RTG-powered powerful rovers...

(music)Must not think, must not think, wet dream bad thinnng...

Posted by: Marcel May 20 2005, 11:42 AM

http://www.space.com/missionlaunches/050520_mars_masterplan.html

Only one MSL ....

Posted by: Redstone Jun 21 2005, 10:07 PM

Source is http://www.lpi.usra.edu/opag/jun_05_meeting/OPAGjun05report.pdf, page 4. No mention of a second MSL.

Posted by: dvandorn Jun 21 2005, 10:43 PM

Maybe flying one MSL at a time is a good idea. Look how badly stretched and incredibly exhausted the MER Team has become, as their babies have survived far longer than anyone could ever have dreamed.

If it were up to me, if I had a mandate to fly a single MSL, I would build two of them and tell people we're going to use one as an engineering testbed. After a successful first MSL flight, we go to Congress and say "Well, jeepers, we have this whole second vehicle that's nearly ready to fly -- how about letting us launch it in 2011?"

That way, the MSL Team would only have to plan and execute an exploration plan for one mission at a time. I know we like all the data the dual MERs have handed us, but face it, it's been hard on the MER Team and their families.

-the other Doug

Posted by: Bob Shaw Jun 21 2005, 11:14 PM

A second MSL which just happens to be available might meet with the same barriers as New Horizons 2...

A Sojourner in the hand is worth a Marie Curie in the bush!

Posted by: edstrick Jun 21 2005, 11:40 PM

They *SHOULD* build a flight vehicle and a "refurbishable" engineering test vehicle. Ideally 3 MSL's should fly at successive opportunities.

Flying 2 identical vehicles in one opportunity increases chances for success, but also for identical failures. The Soviet Venera 11 and 12 landers both had essentially perfect missions till touchdown... and never activated their surface science payload. All they did for the hour plus <I think> they survived is transmit brief batches of descent science from surviving descent instruments <some only returned valid data at higher altitude before frying, as designed>, inbetween long periods of nothing from the inactive surface science payload.

If *I* had 3 MSL's, I'd put one down in Melas Chasma, one down in the geologically most complex and most exposed part of the Meridiani sedimentary complex, and a third down in the deepest part of the Hellas impact basin, where there's complex layered sediments that seem to show plastic flow patterns. There's just too much geologic variety on Mars to fly one and "be done with it".

Essentially identical vehicles could fly the first two missions, the third could have a major update of it's instrument package. If the first fails, it's likely that any simple fix to the design could be done to the second. If we had built 2 Polar Landers, a simple software fix would have probably resulted in a successful second mission. Granted there were additional design deficiencies, like no descent communications, but that could have been patched. A "parasitic" payload could have been attached to the 2001 lander relaying data to an orbiter as during the MER Landings, even if it was only accelerometer data from the parasitic status monitor.

Posted by: BruceMoomaw Jun 22 2005, 01:32 AM

I think both that (A) flying more than one MSL is an excellent idea, and ( NOT flying more than one MSL at any particular launch opportunity is ALSO an excellent idea. It has now been made clear -- both at the Mars Roadmap meetings and the recent European Geophysical Union meeting -- that the main purpose of MSL is to locate trace organic compounds which might be biological at some place on the surface, so that the first sample-return mission (these will be expensive and infrequent as hell) can be sent to that same location.

But if the first MSL comes up empty-handed, we will not have any good idea where to send the SR mission -- unless we launch a second (or even a third) MSL which does find such interesting organics. And if the first MSL does come up empty-handed, it would probably be wise to take some time to decide on the best possible landing site for the second MSL (for which purpose the data from the first MSL will still be valuable).

NASA actually did briefly release the first draft of the Mars Roadmap several weeks ago -- and then almost immediately yanked it back off the Web. It has not yet been returned (whereas most of the other first-draft Roadmaps have been). But I copied it first.

The Committee does recommend unambiguously that a second MSL be flown, but presents two possible alternative sequences of missions in 2009 and 2011. In one, MSL-1 will fly in 2009, and MSL-2 and the first Mars Telecom Orbiter will both fly in 2011 -- which means that the first MSL would have to spend its first year on the surface trickling back data (and driving) at a far slower pace than would be possible with the MTO.

In the alternative scenario, MTO would fly in 2009, while both MSLs would fly in 2011. This seems to me far the superior plan of the two -- both for the above reason, and because, if the first MTO fails, it would provide time to launch a backup one (along with both MSLs) in 2011. (If not launched then, the already-built MTO backup could simply go into storage until it is needed -- which, if things go well, wouldn't be until 2018.) But this scenario does still have the other problem I mentioned: if the first MSL fails to find trace organics, it does not provide an interval to decide the most promising possible landing site for MSL-2 (for which the data from MSL-1, as mentioned, is likely to be important).

The Roadmap calls for the launch of the first of Bush's new "Mars Testbed" missions -- renamed "Mars Environment Mission 1" -- in 2013. (This could be either an orbiter or a lander, depending on which investigations are considered most urgent for the purposes of planning a later manned Mars mission -- its design should be picked by 2008.) It also calls firmly for the launch of the Sample Return mission in early 2016, and "no later". Even if we do that, though, then why not launch MTO-1 in 2009, MSL-1 in 2011, and both MSL-2 and the MEM mission in 2013? We may well end up seeing this sequence anyway, if the Mars program runs over cost (as is virtually predictable) -- and even if it doesn't do so, it seems to me to make more logical sense.

(Two Mars Scouts are called for at some point in the 2009 to 2013 windows; there's a lot of flexibility as to how they could be fit into any of these scenarios. If MSL-1 isn't launched in 2009, the first of these Scouts would definitely fly in 2009 along with MTO-1. It might even provide highly useful additional data in picking the landing site for MSL-1, if it's a trace-gas or water mapper -- and while the Committee doesn't make any firm recommendation, they do suggest that a trace-gas mapper might be the best choice for the next Mars Scout.)

As I say, the Sample Return missions will be so hideously expensive and infrequent that it is absolutely crucial to maximize the chances of their turning up biological evidence -- so a delayed launch for the first SR mission would seem to be much, much better than an overhasty one, despite what the Roadmap Committee says.

Posted by: edstrick Jun 22 2005, 04:08 AM

Missions failures are most often at launch or arrival. Arrival for a lander tends to be a *lot* more likely to cause a failure than for an orbiter.

Granted, the soviets had Mars-4 fail orbit insertion in '73, the US lost Mars Observer during arrival preps in '92 <I think> and Climate Orbiter in '99, and the Japanese had Nozomi fail orbit insertion in '03 after inflight damage from solar storm radiation. But compare that to the US and Soviet/Russian losses in Mars mission launch and landing attempts.

For the '09 opportunity, doesn't the Telecom orbiter launch first?... Orbiters are constrained for a low approach velocity to the planet to cut down on orbit insertion fuel mass and normally launch before a direct-descent lander would.

I'd go for an '09 MSL. If I can't relay through current telecom on Odyssey and Mars Express, then it should launch with the provision that it automatically be mothballed for the '09 window if Telecom orbiter fails to be in good checked-out condition after launch, and be re-prepped for launch in '11.

Posted by: Jeff7 Jun 22 2005, 04:04 PM

Thing is, if NASA only flies one rover, the team will be half the size to begin with, and they'll pare it down as the mission continues. In that event, by the end, they'd only have half the workload they have now, but they'd also have half the staff they have now.

Posted by: Cugel Jul 1 2005, 02:59 PM

As I understand it there are 2 options: a skycrane or a descent stage with the rover on top. The last option having the problem of driving of the lander. But did they ever consider the simple solution of attaching the descent stage directly ON TOP of the rover. What is the problem with this Viking-like approach? After the landing you simply blow a few pyrotechnics and dump the tanks and nozzles of the descent stage on the ground... and drive away. There is no problem of 'disturbing' the landingsite with exhaust fumes because you're not staying there anyway. And with the descent stage and rover firmly connected into a single machine during landing you have complete control over it. Or, put in other words, what is the big advantage of the skycrane over such a simple solution?

I know I'm missing something here... but what is it?

Posted by: Marcel Jul 6 2005, 12:01 PM

Um, well, maybe you forget about the fact that it is not just dumping nozzles and tanks....it's the whole descend stage you have to get rid of. You can't just bolt tanks and nozzles to a delicate rover with it's fragile mobility system hanging under, exposing it to an impact that cannot be controled the way it can be controled on a tether. It even makes sense to let the rover down under a sky-crane AND deliver it to the surface on a shock absorbing platform. Or at least: you have to make the rocker-bogie more rigid to withstand the impact to prevent the wheels to end up besides the rover instead of right under. A temporarily inforced construction that connects the wheels to the chassis with pyros might be a solution as well.

You first need to hover to (almost) a complete stop, then lower it gently to the surface, then let the crane fly elsewhere.

Posted by: Marcel Jul 6 2005, 12:36 PM

Cugel, there's also another thread about EDL for MSL....."skycrane: innovative landing technology"....continuation better be done there, before our iron fisted administrator kicks us out

Posted by: Cugel Jul 6 2005, 08:25 PM

OK! Switching..3...2....1....

Posted by: exobioquest Nov 28 2005, 04:45 AM

I hope wikipedia is up to date on this: http://en.wikipedia.org/wiki/Mars_Science_Laboratory
simple put as: "As of June of 2005 Andy Dantzler, director of NASA's Solar System Division has stated that MSL it is on track for 2009 and he will expend considerable effort to make sure that date is not changed." Has anything come up since then, publicly or not?

By the way I personally think sending 2 MSLs in 2011 is very risky! I have great faith in the skycrane (sure is completely sane compared to the airbag-bounce landing and that worked!) but being un-tests if we sent 2 rovers and they both suffered from some design flaw that’s 140% of the money gone and 200% the PR damage for NASA compared to losing 1 rover in a singular mission. If you look at the history of mars space probes it's most often two identical probes are sent and they both work, or they both fail, not 1 out of 2. So one at a time until we know it works.

Posted by: edstrick Nov 28 2005, 05:56 AM

The Soviet Venera 11 and 12 landers performed nominal missions through atmospher descent (returning excellent science) until touchdown, when both -- IDENTICALLY -- failed to turn on post-landing instrumentation and activivies.
.
. ! oops !
.
What is better than flying two of one kind at the same time is to build more than one, and fly them at 1 opposition intervals. If you design *reasonably* well, most screwups don't require total mission redesign and can be "patched" before the next launch opportunity.

I don't know what the Mars Program reorganization Bruce Moomaw is promising us we'll learn about in his Astronomy article (was it?)..... What I'd like to see about 3 total MSL missions, with a third possibly having a re-selected set of instruments. They'd be sent, as with the current rovers, to as fundamentally different geologic regions as possible within the constraints of focusing on the Martian history of water and potentially life-supporting environments.

NorthEast Meridiani, in the area of greatest differential stripping of layered sedimentary units is an obvious candidate. The Melas Chasma candidate site for the MER-B is another, with spectacularly varied geology plus scenery that rocks. I've been somewhat surprises at the little interest in the layered deposits of Hellas planitia. A potential site might be the lowest place on Mars, NorthWest Hellas, with access to basin floor sediments and cratered highland deposits of the rim (driving might be a bit long-range) I don't want to try for a 4'th time at outflow channel deposits, having failed to find "of interest" with Viking 1 in Chryse, Pathfinder in Ares Vallis, and MER-A on the basalt-covered plains of Gusev

Posted by: BruceMoomaw Nov 28 2005, 07:08 AM

Unfortunately, I still don't feel I can give the information away for free quite yet -- although in another few days it may be a different matter. I will say that the new plan involves something generally similar to at least one more MSL mission, but with a lot of flexibility in the overall mission design.

Posted by: edstrick Nov 28 2005, 09:57 AM

When you're playing it smart, a lot can be done to redesign, even rebuild a spacecraft for an "equivalent" new mission in a relatively short time and at ridiculously low cost. Look at Venus Express, finally sending a "Mariner class" orbiter to Venus for studies that should have been done 20 to 25 years ago.

Another example from Venus: The engineering spacecraft from the Mariner Mars 1964 mission was redesigned and rebuilt as Mariner Venus 1967. The main changes were reversing the solar panels, nuking the camera system (of dubious use for Venus even with plausible modifications), and replacing it with a receiver for dual channel atmosphere occultation measurements to supplement the S-Band occultation carrier transmitted to Earth.

The occultation didn't reach the surface due to atmosphere refraction, but it proved that Venera 4 (arriving a few days earlier) stopped transmitting before reaching the surface, and together with the Venera 4 data, showed the surface would be encountered at around the 90-100 atmosphere level, where it turned out to be.

Posted by: BruceMoomaw Nov 29 2005, 01:21 AM

Believe it or not, there's still a fight over whether Mariner 5's camera (which JPL wanted to fly) should have been replaced by the dual-frequency experiment (which NASA insisted on substituting). In his book "Flight to Mercury", Bruce Murray bemoans the decision, but some article I saw in the 1980s in "Icarus" still defends it.

Posted by: edstrick Nov 29 2005, 08:13 AM

The dual frequency occultation experiment actually turned out to be somewhat "underwhelming". It used longer frequencies than the S-band link to Earth, and because of data recording limitations, only measured the amplitude of the signal and the frequency of the strongest signal being frequency-tracked by the receiver. At the longer frequencies, ionosphere refraction was greater, and one or both channels were refracted enough to cause the radio-occultation equivalent of "mirages": ray-paths got crossed, rendering quantitative analysis of lower altitude data invalid. If they'd been able to record the full signal spectrum, the problem would have been less or maybe quantitatively interpretible.

Radio occultation with receiver on the spacecraft continues to be proposed, as putting a hundred kilowatt continuous wave transmitter on Earth gives a far stronger signal at the spacecraft and higher signal-to-noise than the usual spacecraft-to-Earth link, but since regular radio occultation's nearly free, other than the need for an ultrastable oscillator, it's never made the payload selection.

Posted by: exobioquest Nov 29 2005, 06:54 PM

You people get easily distracted don't you?

What are the possible scenarios?

1. Launch 1 MSL in 2009: If all goes as planned so far.
2. Launch 1 MSL in 2011: If it gets bumped up.
3. Launch 2 MSLs in 2011: Why?
4. Launch 1 MSL in 2009, another in 2011 or later: Why not?

Posted by: Marslauncher Nov 30 2005, 12:48 AM

Cant wait to hear what Bruce knows....


John Cooke

Posted by: BruceMoomaw Nov 30 2005, 02:27 AM

Heh heh heh. Let me take some mercy on you: there will NOT be an MSL in 2011 under the new plan.

Why not? Well, one of the main reasons for the new program design is staring you all right in the face -- you can easily deduce it from what you already know -- but I'M not going to tell you what it is. Heh heh heh...

Posted by: RNeuhaus Nov 30 2005, 02:31 AM

In other topic, Bruce has told that the best option is to send first the MTO on 2009, later by 2011 send two MSL since they will capitalize the widest possible bandwidth of communication offered by the Mars Orbiter Telecom MTO with the new optical communication technology. See Bruce's note http://www.unmannedspaceflight.com/index.php?showtopic=967&view=findpost&p=12936

But as you know that the project of MTO was cancelled? or postponed?, then the most probable best path would be that after MSL 1 in 2009, the next turn would be for MTO along with MSL 2 at the year 2011 or perhaps 2013 depending upon to many factors how is the world is happening in the next years.

Rodolfo

Posted by: exobioquest Nov 30 2005, 02:44 AM

To little money going around, that looks like the problem. There no way they can send a second MSL and MTO in 2011 with the budget given (especially with all the manned space flight crap going on). So then #4 is the most likely answer: they are going to launch a second MSL eventually right?

Posted by: Rakhir Nov 30 2005, 08:12 AM

You should have a look at http://www.unmannedspaceflight.com/index.php?showtopic=1745&pid=29219&st=0&#entry29219.

Rakhir

Posted by: BruceMoomaw Dec 1 2005, 10:03 AM

Note that the findings announced today from Mars Express' OMEGA mapper have shown just why it would be a mistake to pick out a landing site for the first sample-return mission without very careful reconnaisssance. We've often been told, after MER-B's findings at Meridiani, that we need look no farther for a good landing site choice for that mission -- but OMEGA's discovery of patches of phyllosilicate clays are an even better one.

We are by no means sure that life could evolve out of organic compounds in a highly acidic water solution such as produced the hydrated sulfates we see at Meridiani and other places; but the more neutral pH water that produced the clay deposits is a very different matter. Also, it seems that the clay deposits are older than most of the sulfate ones -- probably because the latter formed when Mars was colder, so that only water with a substantial amount of sulfuric acid mixed in from local volcanic sources could remain liquid on the surface -- and the earlier, warmer Mars of the clay deposits would have been more favorable as a location for prebiotic evolution simply on the grounds of temperature. I'm willing to bet that a phyllosilicate deposit of this sort will likely be the landing site for the 2009 MSL, as the best possible place to look for fossilized biological organic compounds. (Of course, MRO's far more detailed near-IR mineral maps will be crucial in picking that spot.)

Posted by: exobioquest Dec 1 2005, 04:50 PM

Is there a global map by ESA of hydrated clay detected by OMEGA anywhere?, be it incomplete or not. All I can find is a example of Marwth Vallis in the Arabia Terra. If MRO also confirms hydrated clay deposites then would that most likely be were MSL will land at (assuming nothing of greater intrest arises)?, or is Vallias Marineris still a prime target?

Posted by: RNeuhaus Dec 1 2005, 05:07 PM

The Terra Meridiani has a mixed materials: Phyllosilicates and Hydrated sulphates. See the report from ESA:

Phyllosilicates were detected by OMEGA mainly in the Arabia Terra, Terra Meridiani, Syrtis Major, Nili Fossae and Mawrth Vallis regions, in the form of dark deposits or eroded outcrops.

Hydrated sulphates, the second major class of hydrated minerals detected by OMEGA, are also minerals of aqueous origin. Unlike phyllosilicates, which form by an alteration of igneous rocks, hydrated sulphates are formed as deposits from salted water; most sulphates need an acid water environment to form. They were spotted in layered deposits in Valles Marineris, extended exposed deposits in Terra Meridiani, and within dark dunes in the northern polar cap.

So the most probably zone with Hydrated sulphates might be closer to Valles Marineris, the Western most of Terra Meridiani. The visiting zone of Oppy must be a Phyllosilicate zone or not since it is located East of Terra Meridiani. isn't it?

Rodolfo

Posted by: exobioquest Dec 1 2005, 05:31 PM

Yes, but I was looking for maps that chart the deposits, all I can find is the one they show of Marwth Vallis. MER-B is about 30° south of Marwth Vallis near the western top of Meridani terra, I’m guessing MER-B is not close enough in Meridani (within a 5 km) to such a deposit, but without a map by ESA of that region were in the dark.

Posted by: dvandorn Dec 1 2005, 09:01 PM

I'll say the same thing I said in another thread -- the ESA spokesman (I can't rmemeber his name) discussing the phyllosilicates said that the closest observed outcrops to either MER are a good thousand miles away. He was asked how long it might take for one or the other of the MER rovers to get to any phyllosilicate deposits, and he said (paraphrasing, my best recollection of his exact words), "Probably Martian centuries -- the closest is about a thousand miles away."

I remember this specifically because I thought it somewhat odd that a European scientist would reference the distance in miles and not kilometers.

-the other Doug

Posted by: BruceMoomaw Dec 1 2005, 10:24 PM

Well, if he was a Brit, he was being nostalgic...

Posted by: djellison Dec 1 2005, 10:51 PM

Well - all the roads and speed limits in the UK are still Miles - it's just the rest of Europe that's converted to KPH

Doug

Posted by: helvick Dec 1 2005, 10:52 PM

As a scientist maybe but them Englanders (well Britishers) are still firmly wedded to miles. Confuses the hell out of me these days when I drive up to Belfast.
:-)

Posted by: RNeuhaus Dec 2 2005, 03:44 PM

I remember that in the decade 80', U.S. has invested lots of money to convince the public to change from miles to kilometers but it was no success.

I would love that any measurements become with metrical system.

Perhaps, that is the evolution direction for near future, all thing will put together with: one currency, one language, one measurement and one goverment. This would be accelareted when the Earth has already colonized in some other planet.

Rodolfo

Posted by: odave Dec 2 2005, 03:57 PM

Canada was much more successful. It seems like everyone I talk to when I'm over there uses metric units.

One time I borrowed a Canadian friend's car when mine was in the shop. His car was bigger than mine, and while driving it I encountered that difference in perceived speed thing. I looked down at the speedometer to make sure I was under the limit and was shocked to see I was doing 100. Then I realized that the large number on the top is kph, with mph underneath. In US built cars, the speedometer labeling is reversed

Posted by: BruceMoomaw Dec 3 2005, 11:11 AM

Well, if that one language ends up being English, I hope we at least have the decency to modify the language to simplify both its spelling and its grammar. As a "Frankenstein's monster" language stitched together out of pieces of Anglo-Saxon, Latin, and God knows what else, it's currently so riddled with numerous exceptions to every single rule of spelling, pronunciation and grammar that forcing adult foreigners to learn it ought to be outlawed by the Geneva Conventions.

Of course, the way things are going, it's at least as likely that the world language will be Mandarin (in which case I hope they get rid of those damned ideograms...)

Posted by: dvandorn Dec 3 2005, 05:20 PM

Careful, there -- oriental languages, which depend on tone to differentiate meaning between otherwise identical sounds, are *much* harder to learn as an adult (for those who did not grow up with such a language) than any other style of language in the world.

-the other Doug

Posted by: exobioquest Dec 3 2005, 07:13 PM

Way don't we all just learn http://en.wikipedia.org/wiki/Esperanto or some modernized more internationalized version?

Anyways I got a question, perhaps I should put it under the MTO cancelled article but I feel this is better due to how off topic you people get. With MTO gone (though jpl still talks about it on there Mars tech page, I guess they will push for it again for 2011 or later) will MSL have a direct to earth antenna, just as a back up at least? Maybe they could just slap one of those on top of the pancam to save weight (use the pancam motors and mast instead of a separate set).

Posted by: mike Dec 3 2005, 10:00 PM

The real issue with language is that it's forever changing, due both to entirely new concepts and inventions and the fact that people just like to make up their own words for things (particularly children). The thing I like about English is that it tends to take the best words for various ideas from all languages and meshes them together. And English isn't so hard to learn that it's impossible for foreigners to understand and speak. I'd much rather have a language like English, which openly changes itself regularly to adapt and become more expressive, to a language like French, where government powers actively try to keep the language 'pure', whatever that means in the first place..

Posted by: Rakhir Dec 3 2005, 10:22 PM

Do you really think that some government actions can have any effect on the evolution of a language ?
Unless in some public services papers.

Posted by: BruceMoomaw Dec 3 2005, 11:41 PM

"60 Minutes" did a marvelous piece a few years ago on the increasingly desperate efforts of the French government to keep the language pure of the vile English pollution -- including an angry debate between two advocates of the idea which ended with one of them yelling "Shut up!" at the other in English. I honestly don't understand why the French are so barmy on this subject.

As for MSL: yep, it has had a DTE antenna added, and you can find an accurate picture of the new setup at http://www-robotics.jpl.nasa.gov/projects/MSL.cfm?Project=3 . (The new antenna will be provided by Spain, and the DTE system adds fully 50 kg to the rover's previous 700-kg mass -- but they haven't had to take anything off to compensate. They are approaching the upper limits at which a Viking-type parachute works on Mars, however.)

Posted by: exobioquest Dec 4 2005, 12:41 AM

Good, though that antenna should only be needed in case something goes wrong with the orbiters, if they need to save weight they can ditch its mast and motors and put it on the pancam, if the pancam motors fail we will loss the antenna but since it is redundant to begin with it should not be as bad as the supersonic shut failing or worth the money of having to design a new one.

If the arm on that preliminary design is what the final is going to look like then it will only have a core drill and a microcam, that means it can sample and run over to another rock while analyzing the sample from the first one! That will be great but I worry about how long the core drill will last and how much CO2 will be available for cleaning the sampling carousel inside the rover. Extra drill bits and an “air” pump will definitely add more weight though the air pump with extra filters could be used to get pure samples of Martian atmospheric dust and could be classified as a experiment in its self.

Posted by: mcaplinger Dec 4 2005, 02:08 AM

First, we call it the Mastcam. Or maybe the MastCam, I'm not sure. The whole mast is generically called the Remote Sensing Mast (RSM), since the navcams and the LIBS (aka Chemcam, or is it ChemCam?) is on it as well.

Second, there's just no way the extra mass and volume of an antenna could be supported by the RSM.

Posted by: BruceMoomaw Dec 4 2005, 02:15 AM

Well, the antenna doesn't have any mast to speak of -- it just sits on a 2-axis gimbal sitting right on the rover's deck. Second, as Mike Caplinger says, it's much too big to be supported by the camera mast. Anyway, the separate camera motors are miniscule in weight compared to the whole DTE system -- you wouldn't be saving any weight to speak of (and probably none, since you'd have to provide a stronger, heavier camera mast to support the antenna as well).

Posted by: exobioquest Dec 4 2005, 03:49 AM

BruceMoomaw

Well I figure the thing was as light as small satellite dish. Forgive me for thinking jpl could at least equal the capabilities of satellite television provider.

When i said mast, I meant the slender vertical structure that holding up the dish in the picture you provided, forgive me if there is some other word for it.

mcaplinger,

Seriously, I feel I may I might have offended you with that suggestion, take no offense I’m not challenging you, quite the opposite: I want to understand. If I ask why not do something differently I’m simply wondering why you did it like that, I’m not trying to make suggestion into a field that is very foreign from my own, rather I’m looking to be answered and enlightened, not respected. If something seems wrong to me I’ll ask the experts why it like that, why it’s not done the way I think it should be, they will hopefully explain to me, I will argue with them until I understand why it like that and then it won’t seem wrong to me anymore. Most people ask why and are given a simple answer, usually they don’t feel the answer was adequate but don’t ask for further explanation out of fear of being embarrassed for some perceive stupidity of not understanding already. I lacking a sense of honor or dignity and I’m willing to make a fool of my self until I understand.

So please don’t get angry with further questions like why not design the “MastCam” to handle the weight, why would two separate structures weigh less then one?

Posted by: mcaplinger Dec 4 2005, 04:33 AM

I think Bruce explained it pretty well. The mass of the motors and antenna is only a small fraction of the whole DTE system (if the total mass of that is 50 kg, they really aren't trying very hard, but that's another story) and trying to cantilever more mass up at the top of the RSM, which has to be stable enough to support Mastcam imaging, has to move rapidly to take mosaics, is a meter or more off the ground when the antenna has no need to be that high -- well, it just wouldn't end up saving mass.

Not the mention the fact that they have to have a fat waveguide between the power amps and the transmitter (presumably in the main rover warm box) and the antenna.

But we're just designing the cameras. JPL designs the mast and its pointing and deployment mechanisms. All I can say is that the RSM design is hard enough to make work as it is.

Posted by: edstrick Dec 4 2005, 07:54 AM

[quote=exobioquest,Dec 3 2005, 07:13 PM]
Way don't we all just learn http://en.wikipedia.org/wiki/Esperanto or some modernized more internationalized version?

I'm TOLD (don't know for sure if it's true but I would NOT be surprised) that Esperanto is no longer the most widely spoken artificial language. That record now goes to... Klingon!

Posted by: Rakhir Dec 4 2005, 08:24 AM

It is just one of the many electoral tactics to win over some types of voters.
Others could say that jobs should be given in priority to native people, or anything else like that.

Anyway, english words are regularly integrated in oral and written french, whatever some people in the government could tell.

Sorry, a little off MSL topic.

Posted by: BruceMoomaw Dec 4 2005, 08:45 AM

Let's hope the French never have to embrace Klingon culture and start talking about the virtues of Blood Wine.

Posted by: exobioquest Dec 4 2005, 08:41 PM

trekkies should be shot for sport!

mcaplinger,

So it should not come to 50kg then? That’s a relief. So basically what your saying is that MastCam is finicky enough as is and integrating the direct to earth antenna would put so much strain on the system that reinforcing all the systems to handle the weight and work correctly would not be economical in weight savings and/or money?

Posted by: RNeuhaus Dec 5 2005, 10:05 PM

Sure, I did have hard time in speaking English in France, specially in Paris since nobody want to listen to English unless French spoken. So I had to speak with hands! Svp un Cafe. (Please a coffee). Svp deux billets de souterrain (Please two subway tickets)... I suspect they understand but they didn't want to listen so.

Rodolfo

Posted by: RNeuhaus Dec 5 2005, 10:15 PM

As my memory does not fail, an previous post, a study that the price to send one kilogram to Mars varies according to the weight of rover. The average price would be around US$600,000. The bigger is the rover, likes ones of MSL with over than 700 kilograms in Earth, taking the advantage of scale economy, the price would drop to around US$ 200,000 per kilogram.



Rodolfo

 MER_C_2219.pdf ( 75.79K ) : 503

Posted by: GravityWaves Mar 25 2006, 05:58 PM

the Zubrinites and Manned-fans think it will get a few cutbacks
http://forum.nasaspaceflight.com/forums/thread-view.asp?tid=1835&start=1
http://www.newmars.com/forums/viewtopic.php?t=3743&sid=c7d1805c3ae262d391219855c31d6f30

Posted by: BruceMoomaw Mar 25 2006, 10:00 PM

During the November COMPLEX meeting, the NASA spokespeople were still swearing on their sainted mothers' graves (assuming any of them have sainted mothers) that MSL will fly in its full form in 2009 -- and that, in fact, they were bleeding money out of the rest of the Mars program to make sure this happens. The new cuts in the Mars program are HUGE -- they amount to over $2 billion over the next 5 years -- but they all involve cancellation of the Telesat Orbiter and Bush's proposed "Human Precursor" missions (whose rationale was always extremely shaky), and the delay of sample return into the mid-2020s.

We are also never again going to see two US Mars missions -- however small one of them may be -- launched in the same window, except perhaps for the pair of scaled-down "Midrovers" being considered for the 2016 opportunity if they don't go for a single bigger MSL follow-up instead. (That means that the current plan calls for only one more Mars Scout after 2011, in the 2018 window.)

Posted by: Mariner9 Mar 26 2006, 06:13 AM

Well, while I would certainly be happy to see more dual launches, like the Mars 96 and 98, and MER, even getting 1 launch every 26 months is still fantastic when compared to a launch to Jupiter every 16-20 years, a launch to Venus every 15, launches to Mercury 30 years apart, .... and so on.

And when you consider the kinds of instrumentation we are flying now, compared to the hardware in the 60s and 70s, we are still in a very incredible period of exploration of the Red Planet.

For the last ten years as I've watched the Mars Exploration program evolve, it has always been in the back of my mind that nothing lasts forever. The day will probably arrive when the focus changes to a new target, or planetary missions get so rare that you can't have a single objet get this kind of attention.

So I just cherish each mission as it gets approved and cheer each time one arrives at it's target. Looks like MSL is a almost a done deal. Mars Scout 2011 looks like it's going to proceed to the selection phase. And from the sounds of things, the 2013 mission is in hot debate in the backrooms of JPL and NASA headquarters.

Things could be a lot worse.

Posted by: gpurcell Mar 26 2006, 02:42 PM

The story quoted above is from May 2005.

Bruce, the Earth-side logisitics for handling TWO MSLs at the same time would be amazing. JPL was really stretched with the two MER rovers; MSL will be much more demanding (simply because it can do so much more).

Beyond 2011, who can really say what will happen. A great deal will rest on the new Administration and the priorities they place in the budget.

Posted by: BruceMoomaw Mar 26 2006, 11:02 PM

There never seems to have been any serious discussion of trying to run two MSLs at one time (which would be, as you say, insanely difficult). What I was talking about was that, up until late last year, they WERE talking about sometimes launching a Mars Scout in the same window as another bigger mission and running those two missions simultaneously. In fact, when Bush's "Mars Human Precursor" program was still around, they were talking briefly about flying THREE missions simultaneously in 2013. All that's gone.

I should also add that the concept of flying two "Midrovers" simultaneously is also very, very tentative at this point -- there hasn't even been any serious study yet as to whether rovers that size could really do the kind of surface studies they want in order to extend MSL's search for actual organic traces on Mars, let alone whether they could run two of them simultaneously (or would want to, given the fact that the MER project came pretty close to driving the staff of JPL into a collective nervous breakdown).

Posted by: mcaplinger Mar 26 2006, 11:19 PM

Oh, I don't know. It depends on what you're trying to do, and how you're doing it (level of automation, etc.) The JPL way has always seemed a bit labor-intensive to me.

That said, they don't enough money for two MSLs, so that's not going to happen regardless of anything else.

Posted by: AlexBlackwell Mar 26 2006, 11:31 PM

In my opinion, the operational constraint for the MERs requiring a separation between the two landing sites of at least 37 degrees of of surface arc undoubtedly complicated the issue by requiring two control teams operating in alternating shifts, resulting in hurried science planning, tired people operating on "Mars time," etc. Note the "37 degrees" constraint was driven primarily by telecom relay from Mars Odyssey since the orbiter can only relay data to and from one rover at a time. In order to optimize orbital relay telecom, the landing sites had to separated enough so that the orbiter "saw" only one rover on any given pass.

I imagine the near-term telecom infrastructure might be able to support simulataneous operations and, as you note, automation could alleviate the load. Of course, increased automation could lead to a decrease in jobs at JPL, which might not go over too well with the workforce.

Posted by: BruceMoomaw Mar 27 2006, 02:51 AM

It's not so much that they don't have money for "two MSLs" -- they just don't have enough money to launch them within 2 years (or even 4 years) of each other. The exact nature of the 2016 mission is wide open, except that it will be the followup to MSL -- it could be two smaller Midrovers, or the more advanced MSL followup "Astrobiology Field Lab" rover, or a second MSL to a different location, or a stationary "Deep Drill" lander to carry out analyses similar to MSL's on material drilled up from several dozen meters down. All this depends on what MSL finds -- and, of course, on money.

In fact, since the biggest purpose of MSL is to locate a place on Mars with enough traces of organic compounds that it would be a good site for a sample return mission, if the first MSL does find such compounds they might not fly a followup at all, but just save the money for the sample-return mission to the same place (which might thus fly 2 years earlier than currently planned). In fact, there's a large minority block in MEPAG who would like to fly the Network Mission instead in 2016 (it's currently set for 2020).