Opportunity Mission Update Thread

[thechemist]

welcome trockner,<br /><br />Mah_FL was talking about the 19-20 Oct. update, which depending on which part of the world you live in, makes a difference.<br /><br />Yoy are both right, the last upload was normal in size, the previous one was huge, and it involved 200 Sol old imagery also, for some reason.<br /><br />Simple reasoning and basic critical thinking are all you need to enjoy your presence in these fora, and contribute too.<br /><br />Cheers. <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[thechemist]

Oppy has seen some serious slippage during sol 262-263.<br />I think it was trying repositioning on Wopmay, or moving towards Burns Cliff.<br />Left is Sol 262 RearHazCam, right is Sol 263. <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[fangsheath]

They must be trying to reposition on Wopmay. As far as I can tell they have even tried to RAT it yet.<br /><br />This area is pretty steep and has a lot of soft soil. I think the reason they have maneuvered away from Wopmay so much is that the rover is above it on the slope, and there is a danger the vehicle will slide into the rock. It is a tricky business - You have to ease your way down to the rock, knowing that the vehicle will slide, and get close without hitting it.

 

[trockner]

Just wondering, but has anyone else seemed to notice a significant increase in image sharpness and/or contrast in at least Opportunity returns since it went back on-line?<br /><br />Maybe its an effect from increased shadowing in the Martian winter?

 

[marslauncher]

Opportunity has driven 1,619 meters (just over a mile). Its latest stop is a lumpy boulder dubbed "Wopmay" inside "Endurance Crater." <br /><br />The daily power supply for each rover comes from 1.3 square meters (14 square feet) of solar panels converting sunlight into electricity. Just after the landings in January, the output was about 900 watt-hours per day for each rover -- enough to run a 100-watt bulb for nine hours. As anticipated, output gradually declined due to dust buildup and the martian seasonal change with fewer hours of sunlight and a lower angle of the Sun in the sky. By July, Spirit's daily output had declined to about 400 watt-hours per day. It has been between 400 and 500 watt-hours per day for most of the past two months. <br /><br />Opportunity, closer to Mars' equator and with the advantage of a sunward-facing tilt as it explored inside the southern half of a crater, maintained an output level between 500 and 600 watt-hours per day in June, July and August. Since early September, the amount of electricity from Opportunity's solar panels has increased markedly and unexpectedly, to more than 700 watt-hours per day, a level not seen since the first 10 weeks of the mission. <br /><br />"We've been surprised but pleased to see this increase," said Erickson, "The team is evaluating ways to determine which of a few different theories is the best explanation." <br /><br />Possible explanations under consideration include the action of wind removing some dust from the solar panels or the action of frost causing dust to clump. "We seem to have had several substantial cleanings of the solar panels," Erickson said. <br /><br />JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA's Science Mission Directorate, Washington. Additional information about the project is available from JPL at http://marsrovers.jpl.nasa.gov/ and from Cornell Uni

 

[trockner]

How much of an effect would lower ambient temperatures have on overall power regulation in terms of heat dissipation? <br /><br />As I seem to recall, even at the Martian equator winter temps could be expected to drop from, say, 50 deg.F to way below freezing at noon.

 

[fangsheath]

Those who are impatient to leave Endurance need to keep in mind that these power generation levels are mainly because we are on the southern wall of the crater. Right now the mid-day sun is about 27 degrees off the zenith here. The rover is tilted, compensating for this considerably. Back in April, when we were racing across the plain, the sun was only about 11 degrees off the zenith at mid-day. On flat ground now we would have much less power to work with than we did then. Within a few months the situation will improve considerably.

 

[thechemist]

fangsheath - <i>"Right now the mid-day sun is about 27 degrees off the zenith <font color="yellow"> here</font>. ...."when <font color="yellow"> we were racing </font>cross the plain..." </i><br /><br />I always suspected that ... <br />fangsheath, you always seemed to know where the rovers are and what they do better than JPL themselves ...<br /><br />Now I know why : you are actually there on Mars !!! <img src="/images/icons/wink.gif" /><br /> <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[JonClarke]

Hi trockner<br /><br />I can't speak for fang but, yes, I am geologist, and having studying the subject for the last 29 years. I currenty work for the government but has also worked for industry and taught at university.<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]

That's exactly what my boss says! But seriously, all of us who get excited about and support planetary exploration are there in spirit. It is hard not to get sentimental about these wonderful robots, our ambassadors in this very foreign land, to root for them and keep tabs on their progress and wish them well, even though we know their days are numbered. But then, everyone's are.

 

[thechemist]

<br />fangsheath: <i>"It is hard not to get sentimental about these wonderful robots..." </i> <br /><br />Don't get me started ...<br /><br />Here, Oppy came too close for comfort to Wopmay. NavCam image 21-10-04<br /><br /> <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[thechemist]

I don't know if it was evident in previous MI images and I missed it, but look at this berry on Wopmay :<br /><br />http://qt.exploratorium.edu/mars/opportunity/micro_imager/2004-10-21/1M151176368EFF36CLP2956M2M1.JPG<br /><br />It seems it has been weathered too, looking like Wopmay itself (a fractal rock ?) <img src="/images/icons/wink.gif" /><br /><br />Note added later : This might have implications on the timescale of the weathering episode, since if the berries were already exposed, it should be later rather than earlier in Wopmay's history. <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[thechemist]

I am almost tempted to suggest fangsheath has cleaned up the dust on Oppy's panels <img src="/images/icons/wink.gif" /> anyway.....<br /><br />During repositioning, Oppy dug on soil rich in a bright mineral, which is attached on its wheels at the moment. Look at :<br />http://qt.exploratorium.edu/mars/opportunity/forward_hazcam/2004-10-22/1F151714921EFF3759P1214R0M1.JPG<br /><br />Is it the same material dug up by Spirit on the other side of the planet ? <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[thechemist]

It seems that Opportunity got into serious slippage trouble: 30cm from Wopmay at some point <img src="/images/icons/blush.gif" /><br />More info from the good guys at this thread in the Mars Exploration Rover Forum .<br /><br /> <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[fangsheath]

If the plan posted there is correct, it is the biggest disappointment of this mission for me. Not so much as a single RAT hole in Wopmay. Must be frustrating for Squyres and Grotzinger. Wopmay could have told us so much. Why didn't they use the RAT when they were in position? Jeez.

 

[anoolios]

While looking at some images on Daniel Crotty's amazing web page, I came across this image from sol 27 (in Eagle crater?), does the rock at the top have the same texture and polygonal cracking as Wopmay?<br /> <br />I too was looking forward to Oppy using the RAT on Wopmay extensively, especially in light of a possible thin surfacal crust, what the heck?... <br />

 

[trockner]

I seem to remember that the RAT can't be used on overly lumpy surfaces because of a difficulty in determining precise distances, or something like that.

 

[thechemist]

Look at this rear HazCam image. It does not look like slippage, but rather like the ground gave way under Opportunity's wheel. It's scary !<br /><br />http://qt.exploratorium.edu/mars/opportunity/rear_hazcam/2004-10-22/1R151714419EFF3754P1301L0M1.JPG <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[thechemist]

Also interesting, is a band of dark berryless soil under and next to Oppy in these NavCam images :<br /><br />http://qt.exploratorium.edu/mars/opportunity/navcam/2004-10-22/1N151715085EFF3759P0673L0M1.JPG<br /><br />http://qt.exploratorium.edu/mars/opportunity/navcam/2004-10-22/1N151715085EFF3759P0673R0M1.JPG<br /><br />http://qt.exploratorium.edu/mars/opportunity/navcam/2004-10-22/1N151715137EFF3759P0673L0M1.JPG<br /><br />At first I thought it was the rover's shadow, but examinations of the 1st and 3rd image shows it is not a shadow.<br /> <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[thechemist]

No RAT on Wopmay, it is official. Say hi to Burns Cliff <img src="/images/icons/wink.gif" /><br /><br />From the October 22 update : <br /><br /><i>"On sol 264, which ended on Oct 21, Opportunity backed away from Wopmay. The planned drive was 2.5 meters (8.2 feet) but the actual drive was 2.57 meters (8.4 feet). Opportunity is now in position to begin its drive toward Burns Cliff."</i> <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[fangsheath]

Such movements could explain the recent change in power generation. On this rather steep slope, a sudden shift in the vehicle's tilt could remove a lot of dust off the panels.

 

[thechemist]

A marsquake might also do the trick <img src="/images/icons/wink.gif" /><br /><br />What about Wopmay's cousin, the ram ? (top on this image)<br /><br />http://qt.exploratorium.edu/mars/opportunity/navcam/2004-10-23/1N151622053EFF3700P1994R0M1.JPG<br /><br />This rock obviously went through the same weathering like Wopmay, plus it has the strangest shape I' ve seen so far.<br /><br />Can sedimentary rocks get that deformed so they look like this? Or is this and Wopmay) a different kind of rock ?<br /><br />Where is JonClark when you need him ? <img src="/images/icons/wink.gif" /><br /> <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[JonClarke]

Your rang sir????? <img src="/images/icons/smile.gif" /><br /><br />To me it does not look as if the basic rock is deformed (folded, feactured etc. Rather the shape of the boulders and their surface textures looks to me more like the results of weathering and erosion. There a arange of interacting processes that can give rocks these shapes - cavernous weathering (the shapes are also known as tafoni), tesselated/pachydermal/elephant skin weathering. Plus of course wind action.<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>

 

[trockner]

Marslauncher...I guess I was just wondering if the Rover electronics/power supplies work better if they're heated or cooled. I would think that the main power supplies (ie solar panel feeds through to the distribution boards) would operate better in a cooler environment., and that might explain why there's an upward trend in net power with the cooler winter temps. <br />

 

[thechemist]

Thanks Jon for your always enlighting comments to the geologically challenged amongst us <img src="/images/icons/wink.gif" />.<br /><br />I think Oppy was not designed to have a wheel sank in sand, no ?<br /><br />http://marsrovers.jpl.nasa.gov/gallery/all/1/f/268/1F151980588EFF37B5P1210R0M1.HTML<br /><br /> <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>