Home Plate Summary Options

[Pavel]

Is there any information about composition of the HP? Why is everybody so obsessed with pretty pictures? Spirit has scientific instruments other than cameras, and I'm sure they were used on the HP rocks. My guess is the information is so sensational that it will be presented on a press-conference, just like finding past water by Opportunity was.

[Shaka]

Is there any information about composition of the HP? Why is everybody so obsessed with pretty pictures? Spirit has scientific instruments other than cameras, and I'm sure they were used on the HP rocks. My guess is the information is so sensational that it will be presented on a press-conference, just like finding past water by Opportunity was.

Hey, Pavel, welcome back, long time no see. Why do you think we're all - Well, some of us! are flaking out here? We drive up to the most amazing sight in Gusev Crater, Steve says, Nice layering! and then goes silent as The Sphinx. The PIs do the spectrometry at one or two spots, but never reveal a word about the results, Spirit then suddenly hauls ass... buttocks up the slope, tiptoes east a few meters, then southwest a few meters, then stops, and the days pictures revert to need-to-know classification! Maybe the analysis is sensational, but why then abandon the place and talk about how cold it's getting? Let's face it, amigo, NASA attracts a flock of conspiracy loonies, but sometimes NASA bears some of the responsibility.
And then there's Exploratorium, but that's another rant...

[edstrick]

Ok... contest: What's the silliest layered gunk we can come up with for lunatik-fringe specualtions on what Home Plate is made of?

How about Baklava?
http://www.yogurtland.com/images/baklava/baklava.jpg

[djellison]

My guess is..

My guess is that they'll still trying to understand the MI images, the PC images, the TES data and the MB and APXS spectra to make the best interpretation of what they'll looking at. Things gont get answered by a single spectrum - they take context, understanding and interpretation.

Doug

[odave]

...and add to that the time factor: Spirit needs to get to McCool Hill before winter sets in. To broaden the context, they'll need to see more of HP. To do that, they need to move from place to place fairly quickly. Adding my guess, they'll try to survey as much of HP as possible, then chew on the data over winter, and possibly return for more in spring, should Spirit still be alive.

[ElkGroveDan]

Ok... contest: What's the silliest layered gunk we can come up with for lunatik-fringe specualtions on what Home Plate is made of?

How about Baklava?
http://www.yogurtland.com/images/baklava/baklava.jpg

How about Chinese Onion Cakes?
http://www.saturdaymarket.com/chinabreakfa...ges/layered.jpg

[tdemko]

Like just about everyone else, I'm waiting patiently for the interpretation of the analyses of the different Homeplate spectra. However, although I usually do not question the planning of the MER scientists and engineers (these people are heroes in every sense of the word), this long delay has made me dwell on the last few big moves, especially by Spirit.

Spirit made excellent progress from the crest of the Columbia Hills to Homeplate, and in fact, the approach to Homeplate seemed down right speedy (they seemed to have been hot on the trail!). Spirit drove directly up to an excellent cross section of the Homeplate strata and did a bang up job of collecting imagery and analyses (hopefully). Then, the bold charge up to the top of Homeplate. So far, so good...

I just finished Steve Squyres "Roving Mars" (wow, what a great book for rover geeks!), and he reiterated something that was said during some of the early MER briefings...that is, that the rovers can do in a sol what a human field geologist can do in a few seconds or minutes.

As a human field geologist, I've always then tried to keep the pace of the MER program into this context. So, here is where my experience would have led me to do the last few moves differently. The "Gibson" locality was pretty much pay dirt for Spirit. Although the Spirit team has kept a stiff upper lip throughout the exploration of Gusev, there has been a palpable disappointment that they did not find the lake they set out to find. This comes across very clearly in Squyres book. That is not to say that Spirit has not done huge science with the materials at hand. The analyses of the volcanic rocks, surficial sediments, and the altered volcanoclastic rocks of the Columbia Hills has been nothing less than fascinating. However, the elephant in the room is a little rover over on the Meridiani Plains literally sitting on a dried out sea bed, surrounded by slam dunk evidence for a large body of water.

Back to Homeplate...Spirit finds a significant section of layered, fairly unaltered, rocks. Bingo! Although my casual interpretations of the images have implied that they do not necessarily indicate the involvement of surface waters, I would not be suprised if there was some evidence somewhere in this section. If I were driving the rover, after the Gibson work, I would immediately have embarked on a circumnavigation of Homeplate to document this amazing stratigraphic section in detail. What are the lateral extents of the units? Are there facies changes? What is the depositional and structural dip of the strata? Are there even better, more complete sections of the strata that give us deeper views into older or younger parts of the stratigraphy?

I understand the need to get a view of the top of Homeplate...but, we could have easily guessed what we see now: the top of the cross-laminated upper unit, eroded and blasted by subsequent impacts. We get some nice views back to the Columbia Hills, and towards the Pitcher's Mound, but all indications are that times a' wastin' and they are already planning long drives into the surrounding hills for the winter. If it were me, I'd want as many analyses and images of the Homeplate strata as possible to chew on before bravely running away. Chances are that Spirit may not make it back...at all.

[Bill Harris]

As a human field geologist, I've always then tried to keep the pace of the MER program into this context. So, here is where my experience would have led me to do the last few moves differently. The "Gibson" locality was pretty much pay dirt for Spirit...

I think the same way. I was disappointed when they abandoned the Gibson site, I would have walked this outcrop southward toward Pitchers Mound and then made it to the top of Homeplate or started the climb up McCool Hill. The was a perfect chance to examine lateral changes in this section.

I'm really itching for Oppy to get moving and on that dark outcrop at Mogollon, I feel that it will be as important as the Gibson locale.

--Bill

[ljk4-1]

My question is, who is really running the show with MER: The geologists
or the engineers? Or management? The answer could explain the
current situation.

[djellison]

Scientists say what they want
Engineers say what is possible
Management say what is fundable

More seriously -it's a case of the engineering team dictating what the scope for rover activities are, and the scientists choosing what to do within that scope.

It's a hard balance. But they've told us for months about the need to get to slopes. The option is to either sit here and try and do science while the rover dies...or...get something quick, get to the good slopes (with actually a quite reasonable chance of a healthy rover in 4 or 5 months ) and then revisit West Spur again.

It's not a choice they're really having to make - the calender and the dust are making it for them.

Doug

[RNeuhaus]

Scientists say what they want
Engineers say what is possible
Management say what is fundable

Everybody think when is possible to go home to care their family and friends. The funneral day would be a mix of feelings.

Rodolfo

[centsworth_II]

I am not a geologist, but as interesting as a circumnavigation of Homeplate would be wouldn't it just provide different views of the same layers? Isn't making a transect of an interesting feature also a typical field technique?

[sattrackpro]

It's not a choice they're really having to make - the calender and the dust are making it for them.

The choice of "get it now, while we can" - or "get it later, after we escape a winter death" is a no-brainer... you act to stay alive, not die taking repeated one-last-looks.

Last winter, we did a lot of sitting in generally one place - but we did drive a bit, and get to new spots to marvel at. We found that drives raised the temperature inside the WEB, sometimes higher than expected - proving beneficial and getting to new places that still gave us the tilt toward the sun needed. I expect we'll see more drives this winter than last.

[dvandorn]

Scientists say what they want
Engineers say what is possible
Management say what is fundable

I'd put it slightly differently:

Scientists say what they want -- as long as it's published. If it's not yet published, they'll threaten you with reprisals if you even ask them what they think.

Engineers say what it possible -- but they often don't care if what is possible is actually do-able within the budget, or if it will actually work in a real-world situation. Or if it will work more than once.

Management says... whatever will make it most likely that, when the excrement hits the air circulation device, no one will be able to point to *them*. And whatever will make it most likely that any failure will result in someone else, and not them, getting fired over it.

-the other Doug

[Shaka]

I am not a geologist, but as interesting as a circumnavigation of Homeplate would be wouldn't it just provide different views of the same layers? Isn't making a transect of an interesting feature also a typical field technique?

Nor am I, sir. (a geologist, I mean) And, yes, a circumnavigation could show exactly the same profile all the way around - but it might not - and under most circumstances, I suspect, that would be unlikely. We have seen two clear types of sediments (see Prof. Tim's lecture on the subject). We would desperately like to see more! We can see that there is not much more on top . There is still a chance that a third kind of deposit could appear at the bottom, somewhere around the edge of HP. This could be just another enigma, but it could also be definitive evidence of what HP is. The emanations from the PIs indicate that impact and volcanic origins are both in the running as to HP's origin. (The PIs already have spectroscopic info that could be definitive, but we don't know that. What they know might make the upper surface of HP much more important.) Another lower unit, however, will be that much closer to the source of the event; it might reveal impact breccia, or volcanic material that would settle the issue.

The recent flock of Mars geology papers show that different people can draw completely different conclusions from the same data! The PI's are going to want very conclusive evidence to support their future papers about Home Plate.