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Stu
I know we've had rather light-hearted discussions about this before, with most people agreeing that Oppy is likely to end her days inside or on the edge of Victoria Crater, simply because there's nothing else to investigate within reach, but has Steve S got it in his mind that Oppy will head off somewhere else after Victoria? This report could be read in a way that suggests that... huh.gif
Sunspot
But isn't the nearest feature of any significance about 20km away? Much more than Opportunities total driving distance so far?
ustrax
"We're going to do a lot of good science, and then we're going to come out again and keep going forward."

ZUPER NUTS!!! biggrin.gif biggrin.gif
fredk
It's hard to conclude much at all from those pitiful few crumbs tossed at the feet of us Squyres-starved disciples. Give us more... we need more... wacko.gif blink.gif

More seriously, we had some clues from Byron Jones a little while ago that Erubus could be a return target.
PhilHorzempa
As prep work, it would be nice to see HiRISE images of the West Rim of
the Big Crater. Then one could ascertain whether layers are exposed or
are covered by dust.


Another Phil
Oren Iishi
[quote name='Sunspot' date='May 28 2007, 02:30 PM' post='91018']
But isn't the nearest feature of any significance about 20km away? Much more than Opportunities total driving distance so far?
[/quo

So pessimistic, 20Km no problem! At some point the exploration of Victoria crater will start to result in diminishing returns. The solar power levels don't seem to be an issue due to the recent cleaning events. In addition, there are sure to be some interesting scientific areas along to route. The hardware seems to be in good shape and I think they should ride this rover til she drops. Also, Spirits seems to be on its last legs and they could allocate those funds for one last push for Oppy.
ustrax
QUOTE (fredk @ May 28 2007, 04:28 PM) *
More seriously, we had some clues from Byron Jones a little while ago that Erubus could be a return target.


If my sense of orientation isn't failing, Erebus isn't forward... wink.gif
djellison
Scientifically it could be. Two, three or more years of sand dunes wouldn't be. Look at HiRISE imagery to the East of Victoria. It's like the worst days of the drive south from Endurance - the area around Jame Caird, Viking and Voyager - an utter driving nightmare made even worse by the fact they would be trying to drive across all the dunes, not along their length..

Unless I see images of that very large crater to the ESE making an EXCELLENT case for going there and HiRISE images documenting the entire route showing it to be in any way feasable - I can see no point in trying to get there when all current indicators suggest it would be a not much more than a suicide mission into a dune field we would never leave.

Doug
MarsIsImportant
Ustrax, I believe the bottom image is a stretched view toward the South. And I believe the satellite image has South toward the bottom. So Ulysses Palace should be on the right, not the left as shown. Did you reverse the rover image? Because if you did not, then you have the lables in reverse. H cannot be H and A cannot be A; rather, H is A and A is H and so forth. Did you reverse that image? Regardless the orientation of the perspective is confusing the way it is shown.
tuvas
During the last HiRISE team meeting, I think it was February, I had the chance to talk with Steve Squires about the future of the rovers. While some things have definitely changed since then (he had told me that Opportunity was likely to enter the then unnamed bay now called Valley without Peril, at a time that would be about a month ago), he had told me then that they are looking for a future target. There is the big crater down to the south, but there are also a few other possibilities, including an outcropping to the west, and a few other areas in the general vicinity. As to which of these will be the final target is still being debated. In fact, there might still be a third as-of-yet unknown place where it might go.

But there are a few things that are going on now that Opportunity didn't have while going to Victoria. First of all, it's faster than it was at the very beginning. Secondly, it's smarter, the recent updates should help get it out of some situations. Lastly, the HiRISE camera could be used to map out the entire route in advance, allowing it to save time not getting stuck in problematic areas. So it is possible that the rover could make it even further than it already has, in possibly the same amount of time. There are several craters that look interesting from previous targets in the southern region. Still, it is a great debate, as to what should happen next.
fredk
Thanks, tuvas, for tossing some very tasty nuggets our way!

I've been wondering how much of a role HiRISE might play in choosing a new target after Victoria (apart from assisting in driving, once a target is chosen). Is it practical to image the surroundings out to some potentially rovable distance, several kilometres say? Are there any plans to do this? Or is the lower-res MGS imagery sufficient to ID good targets?
tuvas
Oh, I have no doubt that before a target is chosen, that HiRISE will not only photograph the potential target, but probably most of the route. As to plans to photograph, well, I really don't know of any, but I don't hang around with the uplink folks that much.
David
It wasn't even possible to have a serious discussion about this question just months ago; heck, I remember a time when even getting to Victoria was absurd, an aspiration rather than a serious goal.

Just to be able to envision going on beyond Victoria illustrates how much these rovers have exceeded expectations.
nprev
Yes... smile.gif ... amazing that there's now concern over sharing S-band DTE channels as well!

MRO's mapping capability should greatly facilitate reaching a new target after Vicky, and that's how it should be; revisits should not be an option without truly compelling justification. The MERs' mobility is implicitly there to see as much of Mars as they can, so backtracking would seem to defeat this rather fundamental design paradigm.
CosmicRocker
I was ready to say that Erebus is a valid future target, and even the most likely one, but that is a good point, nprev. But, returning to Erebus for more science that they know can be targeted requires mobility. too. At this point, I'm not going to guess what they will do. The MRO/Rover synergy probably changes everything.
Bill Harris
Any future target will have to be down-section, away from Victoria's ejecta blanket. That route will give the best science.

--Bill
dvandorn
I think we should look at the entirety of Steve's quote:

QUOTE
"Our adventure continues," he said. "We hope to travel to Duck Bay. If a careful safety review indicates that it's safe to go in, we're going to go in. We're going to do a lot of good science, and then we're going to come out again and keep going forward."


That statement doesn't necessarily mean that Steve thinks they'll be done at Victoria after they're done with Duck Bay. It just means that after they get everything they can from Duck Bay, they're planning on continuing with more observations -- in other words, they're not planning on entering at Duck Bay and ending the mission there. (I take that to mean that if they don't think they can get out, they won't go in. That's reinforced by the mention of a "careful safety review.")

Victoria has a lot more to offer, even after Duck Bay is explored. They've only traversed a third of the crater rim, after all, and there are interesting features counter-clockwise from Duck Bay, such as Bright (nee Sofi) crater and the apparently soil-stripped capes. There are also the Suspiciously Linear Features (SLFs) (take a bow, VP) in the east and southeast walls and floor.

Going forward doesn't necessarily mean leaving Victoria. There are many more things in and around Victoria they can (and likely will) take close looks at after they're done with Duck Bay.

-the other Doug
ustrax
QUOTE (dvandorn @ May 29 2007, 08:30 AM) *
Going forward doesn't necessarily mean leaving Victoria. There are many more things in and around Victoria they can (and likely will) take close looks at after they're done with Duck Bay.


You won...just got this from SS...:
"When I said "forward", I meant it in the figurative sense of moving forward with continued exploration. I didn't necessarily mean that we would continue south."

QUOTE
Ustrax, I believe the bottom image is a stretched view toward the South. And I believe the satellite image has South toward the bottom. So Ulysses Palace should be on the right, not the left as shown. Did you reverse the rover image?


MarsIsImportant, the top image was rotated 90
...and don't trust the accuracy on those marked features... wink.gif
ustrax
I've been bothering SS with the Ithaca issue, like someone distracting the driver from the road and taking his precious time...
Better stop doing that before Oppy makes an unexpected entry at Victoria...

According to SS, although there is, among the team, the curiosity of knowing how interesting that huge baby might be, and the fact of, even through an HiRISE image, the crater would help to make the Meridiani puzzle more understandable, he hasn't looked at it yet...no HiRISE pass is planned:
"If we decide to drive into terrain for which we don't have HiRISE imaging, then we'll get the appropriate HiRISE images."

...And here's a virtue I truly admire...:
"Mars is a big planet, and HiRISE has many targets. Patience is an important part of the game."


Untill that day arrives and I'm still more anxious than patient, I've gathered this image provided by slinted with this MOC image from algorimancer.

Here's the result, the heart of Ithaca:
Click to view attachment
ustrax
And the whole context:
Click to view attachment
djellison
The WHOLE context would show the distance between VIctoria and there - with a scale bar, and perhaps the entire Opportunity traverse to date for reference.

ph34r.gif

Doug
ustrax
QUOTE (djellison @ May 29 2007, 05:16 PM) *
The WHOLE context would show the distance between VIctoria and there - with a scale bar, and perhaps the entire Opportunity traverse to date for reference.


You are mean... sad.gif

Like this?... smile.gif
Click to view attachment
Looks impossible...doesn't it?...
Paraphrasing our dear Nix tow years ago...
I have this vision of Ithaca; it must be one awesome crater up close! Let's hope all goes well, I want to have seen Ithaca! rolleyes.gif
Stu
As much as I love the romance of that idea, it does look a ridiculously far way away to me ustrax... with many months potential dust dune traps and (relatively) featureless terrain to slog through and over before our brave gal finally reached the edge of a crater so big and so wide that surely all we'd see of it from the rim would be teeny mountains stretching across the distant horizon... unsure.gif

I think that when Oppy comes back out of VC she'll be kept busy exploring other features around the rim... Soup Dragon calls, as does Sofi crater, as do a dozen other farside features... there'd be a good chance of Oppy catching changes in the structure of the dunes on the floor with prolonged observation... it would be worth monitoring the outcrops for signs of landslides... so many more reasons for staying, I think, than for striking out for new targets when what is almost certainly the most fantastic scientific site the MER team could have hoped to reach is available.

But hey, who knows what lies out there in the deep desert? smile.gif
babakm
Here's a perspective view from the HRSCView app showing the whole area incl Endurance, Victoria and Big Crater.

Click to view attachment
djellison
QUOTE (ustrax @ May 29 2007, 05:51 PM) *
You are mean... sad.gif


A brutal realist - that's all.

I think it's fair to take the 22 month treck from Endurance to Victoria as a fair measure of progress for a journey of this sort traverse. There will be things that are better ( software and planning) - and things that are potentially worse ( wheels that may break, more broken steering actuators, bad terrain ). Taking Endurance to Victoria (including it's two halts for technical problems etc ) it's a commitment of about 5 years driving. There's not point doing the "100m a sol x Y days = X metres a week" maths - it doesn't work. It never really has apart from primary missions on easy driving ground.

It depends on what HiRISE tells us - it really really does.

Click to view attachment
If it's all like that (which is isn't ) - it's potentially possible.


Click to view attachment
If much of it is like this (which it could well be) - it's madness.

To be fair - the route straight SE from Victoria doesn't look THAT bad to begin with. A few hundred metres of brilliant driving. Then a few hundred metres of typical purgatory-like dunes ( which we have to cross at 45 degrees, not traverse down the length of ) - but then you hit a large region of larger dunes mixed with sparse areas of expose rock - much like the north rim of Erebus that we diverted around by a wide margin - but there's no where to divert to...it's all like that.

Look at it another way - It took 230 sols to get from the Western edge of Erebus to Beagle Crater. About 1.5km - over terrain that looks to me to be a fair sample of typical terrain from here onwards. They didn't hang around very much - they got stuck once - but they averaged less than 10m/sol. Another 20km could potentially be 2000 sols further - or just over 5 years.

I see nothing to suggest it could be done quicker than that - I really don't - and I don't think committing to that sort of expedition is a wise use of the vehicle scientifically - nor within the spirit of the world 'exploration'.

It is a very romantic notion - but one that should remain within our imaginations, unless HiRISE shows little short of a paved highway leading the way there. Don't get me wrong - I would love Opportunity to be able to get there - I just see little evidence that it would be able to.

Doug
alan
Maybe someday the romantics will get their wish and a billionaire will fund a Mars Tourism Rover whose only purpose is to drive long distances over hazardous terrain and take lots of pretty pictures. cool.gif
fredk
You guys want completely uncalled for, brazen speculation? I'll give you completely uncalled for, brazen speculation! laugh.gif

Perhaps we need to think outside the box on this one. Let's suppose we reach a point where it's deemed there's little to be gained staying at Vicky, and that we're still mobile and funded. Let's suppose the "big crater" to the southeast is deemed an interesting target. Instead of driving southeastish, the most direct route there, through what appears to be purgatoryish dunes, perhaps it would actually be far quicker to drive northeast, back to the flat tarmac we had around Endurance, and then skirt east towards the north rim of Big.

In this map I've sketched a route that gets us to the tarmac very quickly from an extension of Vicky's anulus. In total, we'd spend far less distance in dunes than we have in the past. Of course this all depends on how far the tarmac continues eastwards.
Click to view attachment
The circle is roughly where we first got stuck in dunes.
ElkGroveDan
QUOTE (fredk @ May 29 2007, 03:59 PM) *
...suppose we reach a point where it's deemed there's little to be gained staying at Vicky, and that we're still mobile and funded..... it would actually be far quicker to drive northeast, back to the flat tarmac we had around Endurance

I'm with you on part of that Fred, though I'm still way too skeptical about the chances of travelling 20 or so km. But if we have exhausted the obvious science at Victoria, then I could imagine getting back to the "tarmac" as you call it and heading back North or Northeast.

Among some of our tasks could be meteorite hunting (or global impact ejecta), since Meridiani has proven to be a sort of uber-Antarctica in its meteorite hunting opportunities.

Once on the tarmac again we could head back around to Endurance and Eagle, studying the dust deposition and erosion rates on different portions of Oppy's old tracks where we have a very EXACT timeline and season count since the soil was disturbed at each spot.

The chance to examine the chute and backshell site is also something that would excite the engineers among us.
nprev
QUOTE (ElkGroveDan @ May 29 2007, 05:28 PM) *
The chance to examine the chute and backshell site is also something that would excite the engineers among us.


I'd go for that. EDL at Mars is so notoriously (and historically) difficult that it would be well worth the effort to dedicate some intensive study to the heat shield, backshell, and especially the parachute...valuable follow-up data for future missions.
gallen_53
QUOTE (nprev @ May 30 2007, 12:48 AM) *
I'd go for that. EDL at Mars is so notoriously (and historically) difficult that it would be well worth the effort to dedicate some intensive study to the heat shield, backshell, and especially the parachute...valuable follow-up data for future missions.


A bunch of us wanted MER-A or B to take a close look at the backshell. The Back Interface Plate (BIP) and the covers for the Transverse Impulse Rocket Systems (TIRS) on the backshell are made out of SIRCA (Silicone Impregnated Reusable Ceramic Ablator). It would have been very interesting to see how well the SIRCA had held up. However the folks at JPL were adamant that getting anywhere near to the backshell was a non-option because the rover's wheels could have become entangled with the parachute's strings. Fortunately they allowed us to take a close look at the forebody heat shield. That was quite interesting and almost made up for not getting close to the backshell.
Stu
Don't underestimate the value of "pretty pictures" Alan... useful science is the main aim, sure, but it's the "pretty pictures" that make the magazine covers, TV news programmes and newspapers and get the public excited about space exploration enough to cough up the money that allows the scientists to do the useful science inbetween camera clicks.

I think the pics of Tvashtar billowing up above Io, which were adored around the world, proved that only recently... wink.gif
djellison
BUT - there is a point at which there would be criticism for just taking pretty pictures and not doing science smile.gif

Doug
climber
I understand the wish of engeneers to see how the old hardware as behaved.
I thing personaly that we'd better look into the future and use Oppy as another engeneering tester : drive like mad using her software to help future rovers, like MSL. By doing so, we can even imagine more software improvments along the road. As Doug says, we're currently at a mean of 10m/Sol. Can't we drive totaly blind for, say, 10 sols and then assess what has happened? Will we end up will a 10 m drive on the first sol and then get Oppy waiting for more instructions to get out of a trap? Will we end up 1 m to the original target? Will she find solutions we'd not imagined?
I agree that it's not science anymore but didn't John Young did this kind of tests on the Moon?
Toma B
That is why we love MERs so much...there are both science and pretty pictures. Something for everybody.
Stu
QUOTE (djellison @ May 30 2007, 08:42 AM) *
BUT - there is a point at which there would be criticism for just taking pretty pictures and not doing science smile.gif

Doug


True. I wasn't suggesting a Tourism Rover would be a good idea... it would be a stoopid idea actually, all that way just to take pictures; not even I would go for that... I was making the general point that while pictures are probably seen as the cream on the pint of Guinness for scientists, for most of the public and many space enthusiasts they're the tastiest part of the pint. smile.gif

I can do fantastic Outreach with a picture of Oppy sat on the edge of Victoria Crater. A graph showing concentrations of minerals in a rock isn't quite so inspiring to a church hall full of Women's Institute members or Girl Guides or Scouts. tongue.gif
djellison
In the context of Opportunity - a trip to Ithaca would be as much as 5 years of not-very-pretty-pictures-at-all smile.gif

Doug
zoost
QUOTE (climber @ May 30 2007, 07:44 AM) *
Can't we drive totaly blind for, say, 10 sols and then assess what has happened?
I prefer and think that they use a replica on earth to test the software that is responsible for the driving.
ustrax
QUOTE (djellison @ May 29 2007, 06:50 PM) *
A brutal realist - that's all.

It is a very romantic notion - but one that should remain within our imaginations, unless HiRISE shows little short of a paved highway leading the way there. Don't get me wrong - I would love Opportunity to be able to get there - I just see little evidence that it would be able to.


Doug, altough it may not seem like that I can be quite realist too...and trust me I don't get you wrong, I completely understand your arguments and EVEN agree with them... wink.gif
It is far and it is hard, but one thing for sure...it is THERE... smile.gif
climber
QUOTE (ustrax @ May 30 2007, 12:01 PM) *
Doug, altough it may not seem like that I can be quite realist too...and trust me I don't get you wrong, I completely understand your arguments and EVEN agree with them... wink.gif
It is far and it is hard, but one thing for sure...it is THERE... smile.gif

I agree with you, M. Mallory wink.gif


"I prefer and think that they use a replica on earth to test the software that is responsible for the driving"
Zoost, Yes...and No. unsure.gif
djellison
QUOTE (ustrax @ May 30 2007, 11:01 AM) *
but one thing for sure...it is THERE... smile.gif


So is Olympus Mons....when do we start driving? ph34r.gif Sure - it's a long way but...it is THERE.

Who knows - maybe we can find somewhere to set a new speed record (>220m/sol) - but that route to the SE just looks NASTY.

Doug
ustrax
QUOTE (djellison @ May 30 2007, 11:30 AM) *
So is Olympus Mons....when do we start driving? ph34r.gif


Doug...be reasonable... tongue.gif

There is a route that could ease Oppy's way, if we consider that the terrain nearer craters, such as Victoria's apron can be done with no major risk of incidents, then the rover might connect the dots...there are three craters similar to Victoria on the way, if we count with theirs aprons and with the first stretch covering an area where there seems to be considerable areas of rocky ground.
So we would have plenty science to be done on the way...of course that would make Oppy set foot on Ithaca's ground around 2017... wink.gif

Click to view attachment
Thanks babakm!
Stephen
QUOTE (djellison @ May 29 2007, 03:03 AM) *
Unless I see images of that very large crater to the ESE making an EXCELLENT case for going there and HiRISE images documenting the entire route showing it to be in any way feasable - I can see no point in trying to get there when all current indicators suggest it would be a not much more than a suicide mission into a dune field we would never leave.

A crater which a rover can never leave is surely as much of a suicide mission as a dune field it cannot leave, even if the useful science takes a little longer to run out at one than the other.

Or for that matter a crater whose vicinity it can never leave (without "an EXCELLENT case for going [elsew]here" and "HiRISE images documenting the entire route") for fear of falling into another Purgatory-style trap.

QUOTE (djellison @ May 30 2007, 03:50 AM) *
Taking Endurance to Victoria (including it's two halts for technical problems etc ) it's a commitment of about 5 years driving. There's not point doing the "100m a sol x Y days = X metres a week" maths - it doesn't work. It never really has apart from primary missions on easy driving ground.

Gee, Doug, it's a good thing poor Opportunity can't hear you writing the poor thing off like that. rolleyes.gif

I prefer to think of it as following in the footsteps of other five year plans of exploration...
"Mars...the final frontier.
These are the voyages of the Space Rover Opportunity.
It's five year mission:
To explore strange new rocks...
To seek out new sediments and new craters...
To boldly go where no rover has gone before." biggrin.gif

QUOTE (djellison @ May 30 2007, 06:06 PM) *
In the context of Opportunity - a trip to Ithaca would be as much as 5 years of not-very-pretty-pictures-at-all smile.gif

On the other hand, to quote a cliche, nothing ventured nothing gained .

By which I mean that if way back at Opportunity's days at Endurance you knew about those dune fields to the south and the possibility if not probability of the rover getting trapped in a Purgatory would you have been arguing for Opportunity to potter around Endurance instead for the remainder of its days instead of venturing south to Victoria?

The possibility that Opportunity MIGHT get stuck again is (IMHO) surely not in itself a reason for not going to new places to see what science it can do there, any more than the possibility of death was a reason for polar explorers like Amundsen, Scott, and Shackleton to stay away from the deadly hazards of Antarctica.

Are we to start treating Opportunity like a cosseted child wrapped in proverbial cottonwool to protect it from the hazards of life (on Mars)? It's prime mission is long over. Way way over in fact! It is now into extra time. I'd have thought this should be the period when its masters can start to be a little more adventurous with it than they were able to back in its prime mission days. (Plus I also have faith in the ability of its engineers to get it out of seemingly inextricable situations, unlike ye of lesser faith. wink.gif )

======
Stephen
Stu
I think most people here know just how much I live and breathe this stuff, so they'll know how it sadens me to say that striking out for Ithaca would be very bold and noble, and in the 'spirit of exploration' but I think it would be pretty pointless. It hurts me to sound so defeatist, but I just can't see the point, it's a waste of systems and scientific opportunities. Going to Ithaca would mean a journey of - IO think we're all agreed - several years, and those years would be filled with day after day after yawning day of almost unchanging scenery... dunes stretching off to the horizon in an endless sea of ripples, each dune a potential Purgatory... a few rocks here and there, probably meteorites too... sol rise after sol set with nothing new of any note to see or examine... and every sol the chance of a wheel failing, or a system breaking, or a software problem occurring, would grow larger. And all the time the mountainous rim of Ithaca would stubbornly refuse to grow any bigger up ahead. Poor Oppy would be stuck in a Star Trek Voyager scenario... a looooooooong journey to get to anywhere, with death a constant threat, but without the gorgeous Borg in a sprayed-on uniform and the so-annoying-you-could-strangle-him alien cook. wink.gif

Remember the UMSF journey south to Victoria? How we picked up on every hint of a feature on the horizon and obsessed about it for days and weeks? How Doug came close to hiring hitmen to shut some people up? Now, imagine that for FOUR YEARS as Oppy trudges south... arguments over a dozen different beacons... frustration over unchanging scenery after Oppy gets stuck in one dune after another... boredom setting in (and it would, come on, you know it would! I love Mars, but 4 years of dunes would be too much) with week after week of the same scenery...

No. Ithaca would be a great prize (actually, as I type that I'm not so sure about that: it's so big, it would dwarf Victoria, we could only ever hope to see a small portion of it up close, and the far rim would be so far away it would look just like very small mountains on the horizon... hardly a target rich zone for pretty pictures... and it looks so old and weathered that surely the rocks we could study have been eroded greatly... no, I'm not sure it is a great prize...) but there comes a point where someone, somewhere, will have to say "Okay, we've done all we can, but we've nowhere else to go. We plan a long observation mission here, where we are."
ustrax
QUOTE (Stephen @ May 30 2007, 12:08 PM) *
By which I mean that if way back at Opportunity's days at Endurance you knew about those dune fields to the south and the possibility if not probability of the rover getting trapped in a Purgatory would you have been arguing for Opportunity to potter around Endurance instead for the remainder of its days instead of venturing south to Victoria?


Stephen...you got me all emotional, standing up and applauding histerically your entire post! laugh.gif
As it goes on an old Portuguese saying...To backwards urinates the she-donkey... rolleyes.gif
Stu
Admit it ustrax, you just made that 'old saying' up! tongue.gif
djellison
Stephen - have you looked at the HiRISE image to the SE of Victoria?

Please do - then come back and tell me you think heading into that is a good idea - come back and say yes, you think Opportunity can cross 20km of mixed terrain including very large sand dunes with no obvious way around them. I'm being serious. Go and look at it - and can you HONESTLY say you think we can get through it with a vehicle with a stuck steering actuator and a history off getting stuck in fairly modest dunes - three times already.

Be bold, be brave, go exploring - I agree. Jump off a metaphorical cliff? No thanks. This is a PRICELESS asset we're talking about. We can spend another two year at Victoria crater doing good science that we can get to. It's here - it's extraordinary - it's feasable. Then - there's stuff we rushed past at Erebus - we KNOW we can get back there. There's exposed rock that is perhaps 2-3-4km to the SW that would be tough to get to - but it could be interesting. Then there's this crater that's half a decade of driving away over terrain we already know to be hazardous to the MER desgn.

I thought Victoria was a brave option - but appropriately so - a 50/50 shot that was worth doing for the science it might offer. There was nothing left to do at Endurance - it was the best option available given the data available. We didn't know that Purgatory was sat there. Given the data available now - were Opportunity sat at the Heatshield - Victoria would still be the best option. Now - sat at Victoria - Ithaca is not a 50/50 shot. I don't even rate it as a 1/99 shot. It's not a case of 'might' get stuck. Opportunity would have a dozen episodes like Jammerbugt. If we had a Spirit like wheel failure - it would be even harder to get out of those sorts of situations.

With the data we have now - with the evidence infront of us - the orbital images of the terrain to the SE of Victoria and comparing it to the terrain we have observed directly - with a knowledge that the driving wheels have a finite life that has already seen one wheel of the twelve on the surface fail - I honestly believe that saying we should drive to Ithaca is nothing short of crazy - idiotic even.

You may well say 'look - look at that great big crater over there'. I say 'look - look at the terrain we would have to try and cross to get there and look at the years of science we can do right here, now" I'm not saying wrap the thing in bubble wrap...I'm saying exercise sensibility - that's all.

Driving to Ithaca would be - given current data - idiocy. It's a romantic notion...but nothing more - I find it increasingly difficult to take people who think it anything more than that seriously because it shows that you're just not looking at the data infront of us and the experiences of the last 3+ years realistically.

10 years from know perhaps I'll be proven wrong as Opportunity drives it's way around the far rim of Ithaca. But now, with the data we have, heading to Ithaca is the wrong thing to do - and gratuitously obviously so.

In short - cut the romantic crap and look at the best data we have and tell me you honestly believe driving to Ithaca is the best use of this priceless asset.

Doug
dvandorn
OK -- if we're seriously going to discuss where Oppy ought to go after Victoria, I must say I like Fred's idea of heading NW to get back onto the flat, almost-ripple-free terrain that lies beyond the northern extent of Victoria's apron. However, no matter what we do, we run into bad ripple/dune terrain trying to get to Ithaca.

I'd like to suggest a different set of targets. There are three craters of apparently wildly varying ages off to the east-northeast that would make a good site for a co-ordinated study set, which might only take a year or so of traveling to reach (assuming no further wheel malfunctions and the ability to travel 200+ meters a day on good "roads"). Here's my suggestion, overlain on Ustrax's regional map:

Click to view attachment

My proposed route is in blue, here. (Pardon the crudity, I really only have MS Paint with which to work.) Granted, it's nearly as long a traverse as getting to Ithaca, but it traverses over better, far less dangerous terrain, and I see three very interesting targets sort of grouped together at the end of the journey.

The first target to be reached I have labeled A. A is an old, degraded crater about 70% the size of Victoria. It has very much the size and appearance of Erebus, except that is is surrounded not by the etched terrain (which we know now is heavily covered with soft ripples), but with the flatter pavement we found near the landing site. It's an ancient crater, really just a ring of exposed evaporite rim material around a complete crater fill. But unlike Erebus, it's not covered over with obscuring layers of ripples. It seems to me that anything we could investigate at Erebus, we could likely investigate at A.

Just beyond A lies B, a crater roughly the same size as Victoria but with a less obvious apron and without the bay-and-cape structures. Taking a close look at B could answer some significant questions as to why Victoria has developed cape-and-bay structures, while B hasn't -- is it due to differences in the target rock, or is it differences in the erosional process?

Finally, just past B, we have C, which is almost more of an albedo feature than a crater. This one *might* not even be an impact structure -- it's roughly the same size as Victoria and B, but completely lacks a raised rim. Even when an impact structure is completely filled in this area, it leaves a ring of exposed evaporite rim deposits, but C doesn't show any signs of that. It appears to be a sinkhole more than a crater, and seems to be a source of dark dust that is swept out of C and up to the north-northwest. A sinkhole roughly the size of Victoria could teach us an *awful* lot about the subsurface structure of the entire region.

I find nowhere else within possible range where we can see such a diverse set of observation targets, and which can all be studied one after another with relative ease. Each has its own telltale signs of origin and history, and each appears to have undergone significantly different origins and erosional processes -- which is quite interesting, since they're all in fairly close proximity to each other. A study of all three features would, IMHO, give us a far better idea of what processes formed this entire area than looking at the very much more highly shocked remnants of the much larger impact that formed Ithaca. Each also provides variations on what we have already learned at Endurance, Erebus and Victoria, which should help us put those findings in a better regional context.

So -- not only do I see a good set of targets, I see a set of targets that are both easier to reach and at least as valuable to study as Ithaca would be.

What do y'all think?

-the other Doug
ustrax
QUOTE (Stu @ May 30 2007, 12:53 PM) *
Admit it ustrax, you just made that 'old saying' up! tongue.gif


I surely did NOT... tongue.gif

QUOTE
and those years would be filled with day after day after yawning day of almost unchanging scenery...


Not if you follow the three Victorias path... rolleyes.gif

Doug...who's talking about leaving right now towards Ithaca?
I'm quite aware of the work already done and waiting to be done, about the possiblity of getting back to Erebus, and other possible near targets...
But after that?
Is Opportunity going to be parked? Or, time and funds permitting so, embark on a new journey untill it stops working for good?
You are seing the Ithaca journey scenario discussion in a very linear way, as if we were saying that the rover start moving NOW and not stopping untill it gets there...
It's not a journey to Ithaca, it's a journey that might take us there...
Is it so idiotic to think that Opportunity may start a new trek on that direction?
If it gets there, great, if it doesn't there are interesting targets on the way, like the three Victorias, that could enlarge our knowledge about Meridiani...

Let me just add some romantic crap powder and say that this verses will always make an incredible sense to me:

"...
Keep Ithaca always on your mind.
Arriving there is what you are destined for.
But do not hurry the journey at all.
Better if it lasts for years,
so you are old by the time you reach the island,
wealthy with all you have gained on the way,
not expecting Ithaca to make you rich.

Ithaca gave you the marvelous journey.
Without her you would not have set out.
She has nothing left to give you now.

And if you find her poor, Ithaca won't have fooled you.
Wise as you will have become, so full of experience,
you will have understood by then what these Ithacas mean."


K. Kavafis
djellison
I gotta say - those second two craters look damn interesting - and heading NE you get the feeling from the imagery that we'll be on Endurance terrain rather than Erebus terrain once you're at the Ellipse line heading ENE again.

And Ustrax - that's not the case you've been making - you've been saying Ithaca Ithaca Ithaca Ithaca. Not 'lets go to targets in the East and maybe, eventually, we might get to Ithaca'. Go and look carefully at the bottom of the HiRISE image for Victoria ( the larger one that also includes Endurnace ). It's something of a contrast to big 30k wide HRSC images with dotted lines on them smile.gif

Doug
Stu
I know the romantic explorer in you can hear Ithaca calling out to you like a siren sitting on a rock, ustrax, but we have a saying here in the UK too:

Never ye a fool be and poke a sleepy badger in the eye with a stick of rhubarb...

I think that says it all.

smile.gif
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