What's the deal with the hematite calibration targets? Is there anything interesting or significant about them?

http://www.unmannedspaceflight.com/index.p...t=0&#entry27756

MER-B has started analyzing more of the "cobbles" lying on the surface at Meridiani. Are they all -- as seems likely -- basalt ejecta thrown out by very large, distant crater impacts?

Now that you have the experiences equivalent to more than a dozen MER missions under your belt, from an engineering perspective what are some of the design features in the MER rovers that in restropect were baseless concerns? Is there any aspect of the vehicles that looking back your team can say, "well that was a waste"?

Conversely, which features on the rovers that may have been debated prior to final design are you now saying, "Thank goodness we included that!"

Is there a feature or features that designers are kicking themselves for omitting?

On Dec 12th 2005 at the Hyden Planetarium Steve Squyres mentioned that the cobbles were similar to the outcrop rock, except that they contained almost no hematite but did have higher Al, Si contents. He speculated they might be crater ejecta from a deeper strata.

Airbag

At the meeting mentioned above Steve said he would have liked 6-wheel steering, so that the rovers could simply "crab" sideways and not have to do complicated turn&move sequences when repositioning. Of course the weight and complexity ruled that out.

Airbag

There was more on the cobbles at the AGU meeting -- except for Bounce Rock, they are intriguingly intermediate in composition between the light-colored deposits and the basalt, and they also vary a lot in composition. Speculation now is that they are crater ejecta from a different layer of the deposits, which was less modified by water.

A similar thread was opened on the other forum, with a very low S/N ratio.
However there is a single post which, imho, deserves a reference.

"Hi all,

While I am not Steve, I know him and the MER system very well (I was the MER System Engineering manager for MER and one of the project originators).

I would like to take a stab at Bagus' questions: "What have we learned from the MER's to help us build a cheaper, longer-lasting, and more utilizable rover?" and "Would the now tried and true design of the MER's allow us to put 4 MER's on Mars for the price of 2, since the R&D has already been done?"

..."


http://www.markcarey.com/cgi-bin/mt/mt-vie...start=20&show=5

Would that be Rob Manning then?

I just popped over to the other forum to read Rob's reply - Very good...

Had a lurk around - won't do that again!

Makes me realise what a gem we have in this forum.

Thank you Doug for nurturing such a low noise environment.

Nick

Extremely interesting, Tesheiner, thanks very much for posting the link. I hope Rob Manning writes a book about MER (and I wish he could be tempted to participate here).

Googling for more posts on the other form by Marsfriend, I discovered that Doug is an active poster there, which makes me wonder if he has a pet rabbit who can stare at clocks and make them stop. His contribution to this thread was fascinating.

TTT

Correction, USED to be , havnt posted in months, it's just not my sort of place anymore. It serves its purpose, and I'm very glad it exists as it gives a outlet for certain types of poster, but it's not really my thing.


Doug

Me too.

Ouch - is that what everyone calls the "yellow board?" I never really knew what peeps meant by that.

I don't know what hurts more, my eyes or my brain.

And in honor of Rob's blessing of "the other board," I shall now start 32 threads on evidence for Martian coral, streambeds, antenna, fossils, worms and Hyper Dimensional Wind Power in the hopes it will lure more MER team members by here

(I really think he must have gotten his bookmarks file mixed up - I can think of no other explanation)

I used to post to the other place too, but it's not very productive. And if you are at all undiplomatic all you get back is abuse!

As for questions...

With this MER experience of Gusev and Meridiani (but maybe Gusev especially), are there other locations you now wish you had gone to?

and as a follow-up - if you still chose these landing ellipses, are there specific places you wish you had landed in the ellipse - closer to a bigger crater, or other geological unit nearby?

Phil

More gems from Rob Manning.

http://www.markcarey.com/cgi-bin/mt/mt-vie...start=26&show=1
http://www.markcarey.com/cgi-bin/mt/mt-vie...start=31&show=1

-- In any of the sky observation to date from either of the rovers, have any halo's or other refractive phenomena (ice and or dust and apart from releigh mie scattering) been observed?

-- On the artsy/PR Ooooo-Ahhhh front, any thoughts on the feasibility of creating an immersive virtual walk along Spirit or Opportunity's path, something like a virtual version of the walk through that can be enjoyed at Yellowstone?

-- After Home Plate and reaching the north-facing slopes of McCool Hill, what are the areas of interest / science targest that are hoped to be investigated (or more simply, after Home Plate, what is Spirit's 'Victoria' if any)?

-- Roughly when do you think will Spirit leave Gusev crater?

Pertinax

Future Steve Squyres questions.......hhhhhhhhmmmmmmmmm......
I would like to ask Mr.Squyres what he personaly think about this:
Will Opportunity ever reach Victoria crater?
That would be a simple question...answers are only "yes" or "no".

The only valid answer would actually be 'don't know'

Because that's the truth. Oppy might die tomorrow, Oppy might last another 1500 sols. Who knows.

Doug

I will just like to know what he personaly thinks about it...

yes. and therefore the most interesting question is whether there is the intention to at least (earnestly) *try* to reach it or not.
So far it seemed that trying to reach Victoria has always had the lowest priority among any other science goals along the way, i.e. it has always been "stopping as long as possible at each site and driving only as much as necessary to reach the immediate next short-term goal"
while this would be the perfect startegy to maximize overal scientific mission yield
given unlimited rover lifetime I'm afraid that it's different when we take into account the (unfortunately) limited remaining rover life.
So it's really the question if it would not be more advantageous to
try to reach Victoria as a high prio goal first and then use the precious remaining rover life time *there* in order to study what could be entirely new scientific discoveries.
So I'm really looking forward to a change in driving policy after completion of the Erebus/Moggollon study: i.e. drive as much as possible, and only stopping when
something really new shows up on the way.

Wouldn't it be a pity if the Rover would die shortly after reaching Victoria possibly opening a whole new world of opportunities for intersting scientific studies. Then one would regrett all the hundreds of Sols spent collecting all the routine data at less interesting places

Sorry for the long post (about this already heavily beaten topic ... no arguing intended ... it's just that sometime my "thinking/speculating about things loudly" get's the better of me ... ;-)

Let me conclude with the Steve's Squyres own words:


(October 4 Mission Update)

So my question to him would be if, today, he would still maintain this
statement above

So the rover dies in 200 sols, 500m short of Victoria, having done no science for 200 sols

There has to be a compromise, there are unique, new discoveries to be made right here - and to abandom the science we can see, for the science that we may not see, is a nearly wreckless strategy.

Yes - we all want to get to Victoria and see across that new crater and the amazing vista it will offer - but let's remember we may never make it anyway, and to make the assumption that abandoning science where we are will guarentee an arrival at Victoria is wrong.

I'm sure once the work at Erebus is done, we'll see good driving. The arm-issue hasnt helped, but that was a 56 sol period where the decision wasnt down to any choice - it was simply going to take that long to make sure the rover was fit to drive. A few days of festoon observations, perhaps a couple more sites of IDD work around erebus and up to Mongollon rim, then navigating a route thru the remaining etched terrain.

It's the same argument that's been had a thousand times - and I still honestly believe that the only people who can make the right call on the balance between motion and science are those who built the rovers and designed the instruments - only they can judge if the potential for a new target is worth forgoing a local one.

Doug

I'm very sure he and other mission control folk very much want to get to Victoria, but I'm just as sure that if something very different pops up on the way there (moving as quickly as they can to do so) that they will not pass up the stop for good science on any new or different object. You take all you can get as you go, despite a hoped for goal. One thought, there is little diversity expected, but we've been treated to the unexpected frequently - so I would guess we'll be making more stops along the way...

A month ago in mid-Dec, I was so lucky to sit in a room just a few feet from Steve while he was giving his science lecture at the Hayden Planetarium. And I asked him this exact question about Victoria

He said that Victoria is definately "the next big goal and the view would be spectacular". But he "could not predict when or if Victoria is attainable". He said the road ahead looks promising for driving, with a slight incline. I believe he earnestly wants to get to Victoria, having heard it for myself. And the team is always considering the balance between driving and science targets along the way.

BUT, there are too many unknowns. The rovers "may die tomorrow or they may last years". He said there is " battery capacity for ca. 10,000 cycles" for a "theoretical lifetime of 6 to 7 years". A rover killing breakdown can occur at any moment "in the mechanical parts, electonics or due to thermal stresses".

Then, there are the unexpected events like being stuck for 2 months which add more uncertainty. Just yesterday, oppy is finally moving, but looks like slowly and with caution since the team still has uncertainties about driving "elbow out". At the Hayden, Steve was optimistic about this driving mode. But my feeling/impression, is that this problem has taken a bit longer to resolve than he expected in mid-December.

So, Victoria is the "NEXT GOAL" but no one knows if it will really happen

Having said that, I too wish they would move on very quickly and just GO FOR VICTORIA !!

Steve: Which do the folks at JPL prefer during the long stressful hours, LIPOVITAN-D or Red Bull?