Opportunity Mission Update Thread

[cosmictraveler]

I thought it was named after the lingerie manufacturer Victorias Secrets. <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <p>It does not require many words to speak the truth. Chief Joseph</p> </div>

 

[thechemist]

Low clouding over Endurance ?<br /><br />http://marsrovers.jpl.nasa.gov/gallery/all/1/n/240/1N149490467EDN35CYP1572L0M1.HTML<br /><br />or is it a dust devil ?<br /><br />or, - dare I say - water vapour coming from the ground <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[anoolios]

TheChemist, I think (non expert opinion) that is lens flare.

 

[imran10]

A closer look at Victoria Crater. Thanks to Sunspot for posting it at mer.rlproject.com forum. What an odd looking rim!

 

[thechemist]

I could not wait for the approval, and I looked it at the mer.rlproject.com forum.<br />What an amazing picture !<br />The rim looks like it is heavily modified/eroded after the impact.<br />Also, it looks too steep, certainly more so than Endurance.<br /><br />Ah, and did I mention the look of the the etched terrain ? Good things to come, let's hope & pray taht Oppy will continue to operate for a long time. <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[imran10]

Yes it looks really steep but I'll be happy if we get that far. It seems like Oppy will be spending a lot of time studying the etched terrain. The crater (partially seen) on the bottom right looks like it's Victoria Crater (thanks to Doug for posting this).

 

[imran10]

Some 717 new images have just arrived! Enjoy.

 

[thechemist]

Aren't these little chanels in Endurance the result of some liquid flowing ?<br /><br />http://qt.exploratorium.edu/mars/opportunity/pancam/2004-10-02/1P150021606EFF3620P2431L5M1.JPG<br /><br />Have there been any news about them ? Are they recent (geologically) or ancient flows of acid/salty water ?<br /><br />I think these new images show them to look less like cracks between underlying rock layers, as suggested by previous imagery.<br /><br />Anyone heard anything ?<br /><br />Due to heavy workload I haven't been able to follow up the MER missions as close as I would like <img src="/images/icons/frown.gif" /> <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[JonClarke]

I think they are polygonal shrinkage cracks, probably related to temperature change. Note that there are approximately six orientations out of 16 segments and the discontinuous nature of the features. This is consistent with their formation by shrinkage.<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[thechemist]

Thanks Jon. Time for more polygonal shrinkage cracks. Opportunity has reached "The Brain" :<br /><br />http://qt.exploratorium.edu/mars/opportunity/navcam/2004-10-06/1N150376755EFF3649P1968R0M1.JPG<br /><br />http://qt.exploratorium.edu/mars/opportunity/navcam/2004-10-06/1N150382977EFF3691P1998R0M1.JPG<br /><br />which, by the way, appears to be covered with berries, so it bears at least a resemblance to other rocks in Meridiani. I think this rock was mentioned to be distinctively different in previous JPL press-releases. Yes it has an official name, but I am too lazy to look it up <img src="/images/icons/wink.gif" /><br /><br />The huge rock overlooking the dunes also appears to be of similar morphology to "The Brain" :<br /><br />http://qt.exploratorium.edu/mars/opportunity/navcam/2004-10-06/1N150383029EFF3691P1998R0M1.JPG <br /><br /><font color="orange"> Edit : </font>"The Brain" is called Wopmay (?) <br />Is it "pachydermally weathered", Jon_Clark, as Escher before ?<br />The other rock probably has no name. We can call it "The Ram" <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[thechemist]

From this article at Cornell about a Jim Bell (the PanCam lead scientist) presentation :<br /><br />"<i> After exploring Eagle crater, Opportunity took a long trip eastward to the nearest large crater, named Endurance. This impact zone was described by Bell as the "size of the Rose Bowl stadium." Endurance, too, was filled with blueberries. Its greater depth also showed that the water in the area existed way back in the Martian past. <font color="orange">There even appeared to be mud cracks in certain places.</font></i><br /><br />Anyone care to elaborate on what Bell means as possible mud cracks inside Endurance, including pictures of them ? <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[fangsheath]

This rock, Wopmay, does indeed appear to be covered with concretions. To my eye it also appears to be the product of a swelling process, which could explain the pachydermal surface. It looks quite different from Escher to me and I can't image the rover spending less than a week at this magnificent chunk of Mars.

 

[centsworth_II]

<font color="yellow">There even appeared to be mud cracks in certain places.</font><br /><br />Not a well though out statement. First, it leaves open the question of time but definitely allows the impression that the mud may have dried out yesterday. Not helpful when trying to convey an accurate image of Mars. Also, it ignores the possibility that the cracks are the result of thermal expansion and contraction in rock (no water involved, other than in the original creation of the rock long ago). I'm as excited as anyone about the search for water on Mars, but I would prefer the scientists stick to facts and not hype. <div class="Discussion_UserSignature"> </div>

 

[fangsheath]

I agree that scientists need to be careful about loose talk on the subject of Martian water but I have a tendency to cut Jim Bell more slack than most, because he is responsible for the prompt posting of raw imagery that we have come to take for granted, despite the grumblings of his colleagues.

 

[mikehoward]

<blockquote><font class="small">In reply to:</font><hr /><p>he is responsible for the prompt posting of raw imagery that we have come to take for granted<p><hr /></p></p></blockquote><br /><br />If he's reponsible for that, then he's a hero in my book. <img src="/images/icons/smile.gif" />

 

[centsworth_II]

There is a press release Mars Rovers Probing Water History At Two Sites posted by AlexBlackwell giving a much more detailed description of water action and other possibilities for the cracks in Endurance crater. <div class="Discussion_UserSignature"> </div>

 

[centsworth_II]

<font color="yellow">"Jim Bell... is responsible for the prompt posting of raw imagery that we have come to take for granted"</font><br /><br />Thanks Jim!<img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> </div>

 

[JonClarke]

Hi my Chemical friend.<br /><br />Is it pachydermal? I think it could be. Go to the last page of this article http://www.fpb.tas.gov.au/pdf_files/FPN/fpn_issue_21.pdf and judge for yourself.<br /><br />If so it is very interesting as the sprinkage cracks that form pacydermal weathering are due to deydration of clays.<br /><br />Cheers<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[fangsheath]

First close Pancam shot of Wopmay.

 

[thechemist]

"There even appeared to be mud cracks in certain places."<br /><br />This expression was not quoted, so it is certainly not what Jim Bell said, but what the guy that wrote the article (mis)understood.<br /><br />The press release today mentions "mud cracks" as a terrestrial analogue of the pachydermal texture of Escher, so I am quite sure it is a mixup of the article's author.<br /><br />It would seem unfair to attribute the above quote to Bell. <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[centsworth_II]

You're right. Any unfounded water/life hype is usually the fault of a journalist, not a scientist. I don't want to be overly harsh to the journalists either. I count on science journalists to inform me on scientific findings.<br /><br /> <div class="Discussion_UserSignature"> </div>

 

[JonClarke]

Hi TheChemist<br /><br />"Mudcrascks" is a very inaccurate term. It is far worse than "blueberries" which is obviously coined for the lay audience (It is a bad description too, they are neither blue nor berry sized, peppercorns would be a better description).<br /><br />But mudcracks are a specific geological feature. They form when a layer of mud on the bottom of a pond, lake river or tidal flat dries out and shrinks. These features on Escher and Wopmay features are not mud cracks. They are developed on the rounded surface of a rock and clearly cross cut the bedding. Even if they are formed by clay dehydration, mudcrack is a misleading term for them. There may be mud cracks at Meridiani, but they will be parallel to bedding.<br /><br />The significvance of these feature is that, if they are truly due to deydration, indicate water loss of the rock since it has been a boulder, thus much more recently tha the formation of the evaporites, the concretions, more recently than the formation of Endurance. In fact, because they have developed on the upper surface of the boulders they have formed since Escher and Wopmay rolled into their present position. If these cracks are true dehydration features then it is good evidence that minerals in the Meridiani subsurface are hydrated at depths of only a few metres below the surface, or were so recently on the geomorphic time scale.<br /><br />Cheers<br /><br />Jon<br /><br />. While it is likely they are due to they are <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[thechemist]

Hi Jon,<br /><br />Thanks for the pdf link with the pachydermal rock image, it was really impressive. It looks like its skin morphology bares at least a resemblance with Wopmay and Escher. <br />However, as mentioned in the latest JPL press release , other explanations won't be excluded until the full examination of Wopmay with the instruments. That should not take long !<br /><br />From what you said, the dehydration origin of the cracks (if proved) would really push the water story rocket high. In addition to the developing story of the more and more watery past of the Columbia hills.<br /><br />From the above press release :<br /><br />Chemical Changes in 'Endurance' Rocks <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[JonClarke]

Looks like a sodium and chlorine crust on the unaltered and brushed surface that gets removed by the rat. Halite in other words. I have no idea what the zinc enrichment means!<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[thechemist]

This graph from JPL has an error in labelling, I think. Shouldn't 10^0 and 10^1 be reversed ?<br /><br />As it stands, Escher has less chlorine before RAT compared to Virginia.<br /><br />The text from JPL does not help either : <i> "As the red and blue lines indicate, Escher's levels of chlorine relative to Virginia's went up, and sulfur down, before the rover dug a hole into the rocks. This implies that the surface of Escher has been chemically altered to a greater extent than the surface of Virginia. Scientists are still investigating the role water played in influencing this trend." </i> <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>