After Victoria..., .. what next? Options

[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:



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]

Admit it ustrax, you just made that 'old saying' up!

I surely did NOT...

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...

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

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.

[ustrax]

you've been saying Ithaca Ithaca Ithaca Ithaca. Not 'lets go to targets in the East and maybe, eventually, we might get to Ithaca'.

Where did you get that idea from?!

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

Stu, can you please translate that?...

[Stu]

Where did you get that idea from?!
Stu, can you please translate that?...

Sorry, just teasing you, I made it up. But it should be a proverb. It makes as much sense as yours about a backward peeing donkey

[djellison]

Where did you get that idea from?!

Posts 7, 19, 20 and 22 in this thread. Maybe you don't intend to, but it comes across as considering heading to Ithaca a plausable, feasable, and something we should do instead of going back to Erebus or elsewhere

Doug

[algorimancer]

Heading due east from Victoria would indeed be a very bad idea, there is a huge dune field over there. On the other hand, a look at the HiRISE image suggests that there is a route which is initially due south, then curves east through a region which appears generally more traversable than what Oppy covered heading to Vicky.

[attachment=10605:attachment]

There are still some touchy areas to cover, but much of this is relatively open stretches of evaporite. Typically, it looks a lot like this up close:

[attachment=10606:attachment]

[attachment=10607:attachment]

The HiRISE coverage is insufficient to map the complete route in detail, but there's enough to show that Oppy can make it to the edge of coverage without too much difficulty, particularly factoring in the new nav software. As ustrax pointed out earlier,

http://marsoweb.nas.nasa.gov/HiRISE/hirise...SP_001414_1780/

The overview suggests that, once the HiRISE gap is filled-in, a navigable route to the west rim of Ithaca is entirely feasible.

Boring? I think not as bad as prior to Vicky, and the destination is already visible. There will be various outcrops and craters along the way, and lot's of entertainment in projecting where Oppy will go next. Plus Oppy ought to be moving quickly enough to guarantee some regular changes in scenery.

As to scientific value, this takes us into an entirely new geological realm, not only the Ithaca rim peaks themselves, but the interior of Ithaca as well - which the MOLA maps indicate is substantially (hundreds of meters, as I recall) lower than than Vicky, and thus having the potential of having once contained standing water. Taking Oppy in any other direction would just see more of the same fractured/layered evaporite - talk about boring.

Assuming Oppy is healthy at the time, I see no reason why this would be as much as a 4 year trip. Given the new nav software, I could envision completing the traverse in a single driving season, as little as a year. To me, the journey to Ithaca seems to sanest option after Victoria.

[ustrax]

Maybe you don't intend to, but it comes across as considering heading to Ithaca a plausable, feasable, and something we should do instead of going back to Erebus or elsewhere

I believe my posts were not well understood...
When on the way to Victoria were we dreaming about the possibility of reaching Vostok, Argos, Jason or, instead, the mirage of the big crater filled our imagination?
Now, I don't know about others, I'm going through the same process...there are several targets on the way, but the gold is just ahead...
Maybe unreachable, but enticing in such a way that we could trace a path in that direction all this without throwing science overboard.

The overview suggests that, once the HiRISE gap is filled-in, a navigable route to the west rim of Ithaca is entirely feasible.

Boring? I think not as bad as prior to Vicky, and the destination is already visible. There will be various outcrops and craters along the way, and lot's of entertainment in projecting where Oppy will go next. Plus Oppy ought to be moving quickly enough to guarantee some regular changes in scenery.

As to scientific value, this takes us into an entirely new geological realm, not only the Ithaca rim peaks themselves, but the interior of Ithaca as well - which the MOLA maps indicate is substantially (hundreds of meters, as I recall) lower than than Vicky, and thus having the potential of having once contained standing water. Taking Oppy in any other direction would just see more of the same fractured/layered evaporite - talk about boring.

I subscribe every single word in your post algorimancer.

Stu, the old saying means simply the same as...Go Onward!

[djellison]

The overview suggests that, once the HiRISE gap is filled-in, a navigable route to the west rim of Ithaca is entirely feasible.

The MOC imagery doesn't tell the story. The nothern rim of Erebus is an area of HUGE dunes. MOC doesn't show that. We need the actual HiRISE imagery to say what we're going to see. Anything else is conjecture.

I don't doubt the scientific value of Ithaca - it would be extraordinary. I simply believe that looking at the HiRISE imagery we DO have - there are some very very large dune fields with very big dunes with no real way around them. The North seems a far less dune-laden area than the south.

This new software isn't magical - it's not traction control - it doesnt mean Opportunity has sprouted wings - it doesn't make the vehicle less prone to digging in its wheels - it simply gives us the means to identify that loss of motion while under power and terminate drives early ( as we saw at Jammerbugt ). The vehicle would still hit dunes, still get stuck - it just wouldn't do so as dramatically as at Purgatory. There is nothing to suggest the journey of 20km from Victoria to Ithaca could be conducted any more swiftly than the 1.5km journey from Erebus to Beagle.

Fairly sweeping phrases about the terrain to the East and South Algo - my crop of the HiRISE imagery of excellent terrain was from due East of Victoria ( where you say it's terrible ). My crop of terrible terrain was from the South where you say there's an easy way out. I'm as sure that Ithaca is a bad idea as you are it's a good idea.

I think there is a very very strong case for getting HiRISE images (even 2x2 binned) of terrain NE, S and SE of Victoria. All this is essentially idle banter without it.

Doug

[dvandorn]

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.

Don't they? I am *especially* interested in the one I designated C -- its basic form is that of a dimple, rather than a bowl. The light floor unit *might* be some simple dust fill, but as it is surrounded by a "crater" wall that appears convex rather than concave, I have a hard time believing that this is an impact structure, and if it's a sinkhole, the floor might represent a *much* lower evaporite unit than we've seen before. The dark source of the small dark fan *might* just be a dust trap that occasionally yields part of its trove back up to the winds -- but it might also be a piece of a darker, different type of material that's eroding into dark dust.

Yes, Ithaca's ringwall remnants could be quite interesting -- but what are the odds that Ithaca was emplaced a *long* time before this part of Mars was repeatedly flooded, and has been altered so much that you'd have to spend a decade putting together it's story? Ithaca *might* give you some insight into what existed here before there was water -- the three craters I'm looking at, it seems to me, might offer a better chance at increasing our insight into what this part of Mars was like *while* there was water here.

Is it just me, or does it seem like that would be perhaps a little more useful?

-the other Doug

[babakm]

The area directly South of Victoria looks pretty bad in the HIRISE shot, but once you get past that (easier said than done), it looks like the plains North of Victoria again (especially in the SE corner of the image). This HRSCView image is the best available to look around in the area.

As Doug said, we need many more images.

[algorimancer]

My crop of terrible terrain was from the South where you say there's an easy way out. I'm as sure that Ithaca is a bad idea as you are it's a good idea.

Incidentally, there are 3 attached images with my last post which are not displayed. When I go into full-edit I clearly see the attachments, both the files and the associated tags in the post, however none of them are showing above. Something gone awry with the site?

Here, I'll try again:




The first image shows an overview. I used red to indicate regions of heavy dunes, between which is a region of mottled terrain, close-ups of which are shown in the two follow-up images. Yes, as you say, there are regions to the south where the terrain is very bad, yet in the midst of the bad are regions which are pretty good.

I appreciate that we have very different notions as to the wisdom of heading to Ithaca . It is too early to commit to it, Oppy may not survive that long, and I agree that we definitely need HiRISE to pave the way. Still, it's a heck of a lot of fun to contemplate.

[gallen_53]

I think MER-B should aggressively explore Victoria Crater. Victoria Crater is a good place to die (much better than the middle of a dune field). Aggressive exploration up the sides and along the edges of the crater would show us the limits of the rover's capability. Such knowledge would be useful towards guiding future rovers.