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Unmanned Spaceflight.com > Mars & Missions > Past and Future > MER > Opportunity
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djellison
http://mer.rlproject.com/ohsc.jpg
centsworth_II
I bet there are lots of "mystery fibers" on the ground in this area!
mike
Those are pretty sweet.. the engineers must be loving them.
djellison
hendric
Being a fellow engineer, I imagine the heatshield team must feel a small hint of sadness seeing something they worked on for so long in so many pieces...So I thought a haiku might cheer them up...

Broken and shattered
Upon the field
Job well done
djellison
Possible evidence for wind at Meridiani?



Thats all the filters, just run one after the other.

I'd like them to get a little closer to this piece - simply so we could get a self portrait looking at the foil - parts of which look quite flat smile.gif

Doug
remcook
what's the white stuff flowing across the image? if it's dust it looks a bit light doesn't it?
OWW
The white stuff are reflections in the camera. Doug means the shield 'moving in the wind' I think. What is it made of anyway? Can aluminium move in such a small breeze?
djellison
I dont mean the foil, or the glare from the camera smile.gif I mean the big piece sticking up from the heatshield - looks a bit like an old cable or something smile.gif

Doug
CosmicRocker
Wow! That thing clearly appears to be moving, and wind is the only likely explanation. There is just one thing that confuses me. If the part is in different positions in the red, green, and blue filters, shouldn't your colored image above show some color separation or blurriness on that same part?

I'm curious. Did you do an animated gif for the whole image, and if so, did you see any other signs of movement?
Pando
I think they are currently looking for signs of movement due to wind; basically looking for stuff being blown around. I don't know if anyone has actually found any conclusive evidence of it but Doug's gif is certainly quite interesting.

If Geoffrey Landis is reading this forum perhaps he could run this past the atmospheric science folks?
djellison
QUOTE (CosmicRocker @ Jan 4 2005, 03:46 AM)
Wow! That thing clearly appears to be moving, and wind is the only likely explanation. There is just one thing that confuses me. If the part is in different positions in the red, green, and blue filters, shouldn't your colored image above show some color separation or blurriness on that same part?

I'm curious. Did you do an animated gif for the whole image, and if so, did you see any other signs of movement?

I did think that myself - but the movement isnt really enough to see seperation in the colour. I did check the whole image, and there wasnt anything else moving that I could see.

Doug
slinted
QUOTE (Pando @ Jan 4 2005, 04:33 AM)
I think they are currently looking for signs of movement due to wind; basically looking for stuff being blown around. I don't know if anyone has actually found any conclusive evidence of it but Doug's gif is certainly quite interesting.

I was wondering why there were so many duplicate sequences on the recent sols, like the one Doug used for his gif. Looking at Opp sol 335 ( http://www.lyle.org/mars/bysol/1-335.html ), they took a L4567R1 series, then did another right after. In looking at the times in particular, that piece is wiggling back and forth between just about every frame which
are seperated by as little as 40 seconds and as much as 1 minute 20 seconds.

I'm not sure if its all shadow changes or not, but it seems like there is a difference in the general shape of the heatshield section between the 2 R1 frames, seperated by 2 minutes 20 seconds : http://www.lyle.org/~markoff/collections/oppsol335R.gif
akuo
Sure looks like wind to me.

This got me thinking, Oppy doesn't have a weather package, but couldn't they have tied a small flag or a piece of string or something on the calibration target post? At least this way they could have looked indirectly for wind.

Another technical improvement came to my mind earlier. Since the rover gets much better solar coverage when tilted towards the sun, then why not make the whole rover tiltable? This should be possible to implement in the rocker-bogey wheel system. It sort of seems to me that JPL didn't think of the orientation of the Rover in its plans, since they had the HGA motors freezing in the shadow of the mast on one of Spirit's fist sols - only after this even they started turning the rover to the most favorable position after each drive. This manouvering could be extended to tilting the rover also, if the mechanics existed.

Of course this would mean more careful manouvering around targets on the ground, but it would still improve the solar power situation most of the time. Maybe it could be considered in future missions, even Phoenix (by making the legs party movable in vertical direction). I think JPL will also put some thought in making the MSL solar powered after all :-).
chris
It would probably be less complex to make the solar arrays tiltable.
Bill Harris
QUOTE
Being a fellow engineer, I imagine the heatshield team must feel a small hint of sadness...


But look at it as the ultimate in destructive testing. smile.gif

Great discussions here. Thanks!

--Bill
djellison
It does look like the whole thing is rippling a little in the breeze http://www.lyle.org/~markoff/collections/oppsol335R.gif

HOWEVER - remember - even over that short period the sunlight angle will have changed ( look at the shadow ) so it may be partly due to the sun moving a little - and partly due to wind

Doug
MizarKey
I favor the wind theory...check out how clean Opportunity is:



Eric P / MizarKey
OWW
It seems others are noticing the 'wind' too:

http://www.markcarey.com/mars/discuss-2174...stone-rock.html

Look at the 'movie' in the January 4, 2005 02:50 post by hortonheardawho.
djellison
QUOTE (chris @ Jan 4 2005, 11:59 AM)
It would probably be less complex to make the solar arrays tiltable.

Well- the actuators are almost there already to tilt the vehicle back and forward - so all that would be required is a means to command that specifically.

However - the next rover on mars will be RTG powered anyway biggrin.gif

Doug
chris
Assuming, of course that the skycrane does its stuff (and I thought the MER landing were scary)
djellison
I didnt say succesfull lander - I just said lander smile.gif

The last non-roving vehicle on mars wsa Beagle 2. It may be a small crater and some schrapnel - but it IS there smile.gif

FWIW - I trust JPL to deliver with Sky Crane.

Doug
djellison
I was thinking about trying to reproduce this area in 3ds max - i.e. take bearings and ranges of navcam and pancam to reproduce a map that shows where everything is - then use that to build a 3d model of the debris on top of it.

Anyone got any thoughts on that?

Doug
Sunspot
I wonder if they are planning on getting a closeup look with the IDD at this rock:

http://qt.exploratorium.edu/mars/opportuni...BYP0725L0M1.JPG

Looks different to Bounce rock way back near Eagle Crater. That's an image from navcam, no pancam shots of it yet.
MizarKey
QUOTE (djellison @ Jan 5 2005, 02:34 AM)
I was thinking about trying to reproduce this area in 3ds max - i.e. take bearings and ranges of navcam and pancam to reproduce a map that shows where everything is - then use that to build a 3d model of the debris on top of it.

Anyone got any thoughts on that?

Doug

With my limited cranial resources I can't be of much help sad.gif , but I would love to see what you come up with.

Eric P / MizarKey pancam.gif
Marcel
QUOTE (djellison @ Jan 5 2005, 10:33 AM)
I didnt say succesfull lander - I just said lander smile.gif

The last non-roving vehicle on mars wsa Beagle 2. It may be a small crater and some schrapnel - but it IS there smile.gif

FWIW - I trust JPL to deliver with Sky Crane.

Doug

Talking about MSL: Why didn't they include a small RTG on the MER's ? It is so amazingly valuable what they produce. The mechanical durability of the machines is known by all engineers: as long as energy is not the problem, the actuators, bearings and avionics can last muuuuch longer than 90 sols (which the machines BOTH proved). It would have been so cool to know that dust built-up is not going to be the problem. Consider what it would be like to know that even if the solar arrays would be full of dust, they still could go on (maybe on a slower pace due to the small nuclear source). Is such an RTG that heavy ? Can't they built small ones with like 0,5 kW of output ? Seems to me (considering the plans for MSL) that even rovers of 900 kg can be launched on a delta4.....so an RTG on MER could have been an option.
By the way: they are probably going to built TWO MSL's !! Wow, good idea ! rolleyes.gif
Analyst
RTGs are better than solar arrays from an energy point of view, no doubt about it. But they are quite expensive, probably because so little are produced. And there is a lot of trouble because the general public often thinks all people in Florida will die from the radiation if the launcher explodes (I remember the Cassini launch in 1997). Also, maybe their radiation could spoil MERs instruments without protection.

One Voyager RTG has a mass of 39kg and generated 150W at launch, after 25 years abaut 100W. That's quite light for 2.400W/hr (!) per day (and night) after this long time. So MER could have used it. 39kg is about 1/4 of the total rover mass. But you don't need solar arrays! 0,5kW is really big.

Concernig the launcher: MER used a Delta 2, MSL will need a Delta 4 or Atlas 5, much larger rockets.

Analyst
Pando
Actually there are radioisotope units on board the rovers, eight of them, but they are used for heating and not power generation.

http://marsrovers.jpl.nasa.gov/mission/sc_...mp_heaters.html

Main reason is probably that the whole thing was designed as a unit, and it doesn't make sense to include an expensive, heavy power system to a rover that has other systems (wheels, gears, science instruments, etc) having less designed lifetime. In other words, to really make use of the RTGs, all other components must be designed to work for extended periods as well, increasing the cost and design time of the rover beyond what was budgeted and needed.
jaredGalen
In this image from the rear hazcam, in the middle track of the three wheel tracks shown, is that a hole near the left wheel?
It seems unlikely that a bit of stone got stuck on the wheel, and got plucked out of the ground seeing as it is lined up with one of the threads.

Or am I just looking at it wrong. It does look like a hole though.....

Edit: I guess it could be a piece of black material from the shield...but it still looks like a hole . smile.gif

http://qt.exploratorium.edu/mars/opportuni...CLP1311R0M1.JPG
OWW
Oppy approached the main part of the heatshield. Good view of one of the springs:

mook
Oppy's playing in the trash:

mike
Opportunity is perplexed.. from whence did it come? Is this a clue, or is this just more amazingly detailed debris? Perhaps if it lingers long enough, it can figure something out..
slinted
Here's a mosaic of 5 frames (its interesting that they shot every one twice, with different exposures...these are the ones with the least blooming) of what will no doubt be a much larger mosaic, hopefully in living color soon enough:

http://www.lyle.org/~markoff/collections/oppsol339L7.jpg
djellison
That two-shot technique is analagous to taking multiple exposures on earth to simulate HDRI imagery I guess.

Doug
Bill Harris
Wonderful!

Take a look in the left center on the rim of the heatshield... you can see a loose piece of insulation flapping in the wind.

http://qt.exploratorium.edu/mars/opportuni...C2P2368L7M1.JPG

They do seem to alternating between R1 and L7 exposures, I guess they're building stereo pairs.

--Bill
OWW
Thanks. Here are the links to the two pictures. Must be the wind ( unless Oppy touched the heatshield with the arm before taking the second picture ) :
http://qt.exploratorium.edu/mars/opportuni...C2P2368L7M1.JPG
http://qt.exploratorium.edu/mars/opportuni...C2P2368L7M1.JPG
djellison
LOL - one even has motion blur smile.gif How long before the cooks show this as evidence of martian gremlins wandering around wink.gif

I'm amazed that they've driven so close to this piece - as there is a large ( several feet across ) 'flap' of insulation that has peeled away from this area and looks to be folded around to the left. It could quite easily fold itself back again ohmy.gif

Keep an eye out for the self portrait - i.e. reflections of Opportunity in the foil smile.gif

Doug
OWW
QUOTE (djellison @ Jan 9 2005, 11:45 AM)
LOL - one even has motion blur smile.gif

Hmmm. The thingies on the left in this picture. Motion blur too? They look a bit fuzzy. Especially the large thingie on that 'peak'.

OWW
Another view of that 'peak'. Is it really motion blur, just fibers, or both?

Bill Harris
This is fascinating, to see the effects of the Martian wind first hand. Last week we the stacked GIF animations of parts moving and the insulation blanket rippling and now close-up we see parts moving quickly. I guess there _ought_ to be concern about the loose insulation blanket whipping around. Winds from thermals (dustdevils) can come from any direction at any speed.

I guess this is proof of the Ghosts of Mars... rolleyes.gif

--Bill
ilbasso
Also interesting to note in the pictures that ObsessedwithWorlds referenced (in his Jan 9 09:00 post) that you can see one of the separation springs still attached, under the curled-over piece. I guess that explains why we couldn't count all of them lying around on the soil.
Sunspot
Hey we finally have a fairly closeup look at the rock near the heatshield debris

dot.dk
That's one weird looking rock! blink.gif
SFJCody
Meteorite?

Tektite?

Bounce #2?

Lump of ejecta from Endurance?

Big piece of cheese?

Place your bets now!
Bill Harris
It looks almost meteortic with those pits on the surface. But it looks light through L7/R1, so it isn't reddish in color.

My impression is that to looks like a piece of limestone from an anoxic limestone drain. That is a process where you add alkalinity to acid mine drainage by letting acid water flow through limestone fill. So it may be an evaporite dissolving in groundwater?

Not totally serious, this is my first thought. We'll know more once we get more images.

Whew.

--Bill
CosmicRocker
At this point, I must vote for cheese...most likely a piece of green cheese dislodged from our moon in an ancient impact.

Seriously though, it is a fascinating rock. I don't see how we can leave without taking a closer look. Probability would favor it being a chunk blown out of Enduarance, but I see no signs of blueberries. There is a small area that sugests fine scale bedding (maybe even a cross-bed), and another area with a vug resembling some seen at Eagle Crater and Endurance, but for the most part, it looks exongenous. I guess that would cause me to vote for Bounce 2.

I'm not going to bet the bank on that, though. I'd like to at least see some other filters, but I am hoping for MIs and an APXS.
Pando
Looks like Oppy is really busy creating a monster MI panorama from the edge of the heatshield blink.gif

Pando
It's alive! blink.gif laugh.gif

slinted
QUOTE (Pando @ Jan 11 2005, 01:49 AM)
Looks like Oppy is really busy creating a monster MI panorama from the edge of the heatshield  blink.gif

Rick Coffin at www.whatonmars.com did a mosaic of the MI frames:
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