As the file name suggests, that is one of the three images taken by the descent image camera to measure horizontal motion and allow it to be cancelled out during the final stages of descent.

Phil

Ah, "Descent Image Motion Estimation System", intuitive once it's deacronym'd. PIA05146. And now I've gotten a proper non-jpeg'd TIFF.

Hmmm, you don't suppose that the shadow in a hotspot to the left of Endurance Cr really is a hotspot and shadow???

At any rate, here is a ground-truth demo comparing a crop from the DIMES image 3 and one of the MER-B polar Pancam panoramas (although one of my source/ working images is labeled "MOC" instead of "DIMES").

You can see that there is a preferred orientation to these things, even several kilometers away.

--Bill

I can't quite beleve we are talking about this again nearly a decade later, but that 'hotspot' is the opposition surge with the shadow of Oppy's parachute near the centre.

The enduring legacy of MER...

I found this interesting thread:

http://www.unmannedspaceflight.com/index.p...95&hl=dimes

--Bill

Back to 2013! This is the current position, a comparison of HiRISE and the 3353 Navcam partial pan in circular projection. A red spot shows the current location. Since they have made such good progress, maybe there will be a brief examination of the bedrock just ahead over the upcoming holiday.

The dark streaks in HiRISE are seen in the Navcams to be dust drifts.

Phil

Click to view attachment

Any idea where site Tawny is located?

No - what's it from? The latest Pancam targets?

Phil

I concur, so you do not just need to feel about it my friend.
In the early part of the mission the rover did encounter several cracks that indeed were interpreted as signs underlying karst terrain, and that some now have been found to be associated with Endeavour crater could be a hint it have formed in cracks and areas where the bedrock have been shocked which gives us a bit of a timeline on the formation here. Even though the actual dating could be rather 'rubbery' indeed.

It's challenging to locate because the images haven't come down yet, but "Tawny" is the target that Oppy examined with the arm on Sol 3352. She briefly backed up and captured Pancam images of it on sol 3353 before moving on.

I think it's important to note that the cracks back in the pre-Victoria days are on the surface of a sedimentary stack hundreds of meters thick, while the cracks around Endeavour's rim are in a relatively thin layer of sediments covering the rim -- perhaps only a few meters thick in some spots. The near underlying rock in both cases is totally different, so the processes resulting in the cracks on the surface is likely different as well.

For example, the karst explanation may work well for the earlier terrain while the cause of the Endeavour rim cracks could more likely be the result of slumping of the underlying crater rim or differential expansion/contraction of the thin sulfate surface layer and the underlying rock of the rim.

Just my meagerly informed musings.

The wetting/dessication cycle could be one in tens of thousands of years (orbital/precession cycles), and still be effective at creating "active" features in this profoundly ancient landsacpe.

Oh, agreed wholeheartedly. The Anatolia features seen early on and these lineations seen here are of the products vastly different ages, processes and Mars'es (climates). Especially intriguing is the terrain to the east within Endeavour which has many AnatoliaFeature-like characteristics but with a different genesis.

And doubly especially the thin, persistent (over a few kilometers at least) unit of the Meridiani Onlap which represents an unconformable contact between the old weathered and reworked impactites of the"Endeavour formation" and the newer sedimentary clastics of the basal Meridiani formation. This is a unique instant in geological time and we need to be looking at the ground under our boots to hear it's story...

--Bill

Master of the understatement.

It's in this vicinity:

--Bill

At the scale of a HiRISE image Tawny can be located a bit more precisely than that, Bill! It was within reach of the arm on sol 3352, and Opportunity was driving backwards with its arm on its north side at the time, so Tawny is a pixel or two on the north side of the sol 3351 location. It's at the scale of the rover camera mapping that we don't yet know where it is

Phil

But without FHazcams w/ the IDD deployed or the Pancam sequence we won't know exactly where Tawny is.

I guess it may be in this locale

http://www.midnightplanets.com/data/MERBRa...R9P1205L0M1.JPG

and zooming in on the HiRISE image I can pick out which of several rocks it might be, but not exactly. But I'll guess when we do get a peek at it, it'll be almost earthshaking...

--Bill

As Phil says, "Tawny" is near the sol 3351 marker (assuming that's in the right place), facing SW from the rover. This sol 3351 Front Hazcam image should show it: 03351/1F425685490EFFC3NLP1214L0M1.

But I'm not sure "Tawny" was much of anything; they might just have been checking out the arm after this potentiometer issue mentioned in the latest rover update.

The feature you're interested in (post-drive on 3353) doesn't have a name yet, that I'm aware of. (Well it might have a name that we don't know about, but you know what I mean: there are no Pancam images of it the metadata yet.)

Yes... I guess... we're just going to have to wait.

<MOD HAT ON> Very funny, all, but let's try to stay a bit focused, eh?

The opstempo right now is a bit (well, quite a bit) more leisurely than previously. So, we're gettin' a little bored in the long intervals between new events. Understandable & natural.

Unfortunately that means that the SNR of this thread is decreasing thereby. I don't think it's intentional at all, but nevertheless it's happening.

So...just a gentle (and I do mean that) reminder to try to focus a bit more on the observations & the science. That's all.

</MOD>

I'm not sure what your point is, because this is a MER thread.

The point is that I'm an idiot, I'm really tired (tough couple of days, in the middle of a temp schedule alteration) & screwed up. Post modified; thanks, Mike!!!

Not totally clear what happened on 3335 - we have rhaz but no fhaz down. The latest blog entry at the end of this (very long) blog saysSo no fhaz because no turn?

That one rear hazcam must have been good though; they drove another 25m on it on sol 3356 (with autonav). That's after over 116m on sol 3355, plus taking a bunch of images along the way.

Bill and Phil: the crumbly rock on sol 3353 is now named "Lake Eyre". They got an L257R2 of it before zooming off.

The layers at the sol 3356 site (176/0158) are beautiful. Here are very quick Navcam and Pancam anaglyph views.

Yes! Lake Eyre.

And tosol's (Sol-3356) Drive Dir Pancams show the wonderfully delicate remnant bedding underfoot (-wheel). We may start seeing significant changes in the outcrops over the next few drives.

One of those Pancams in your anaglyph, for reference:

http://www.midnightplanets.com/data/MERBRa...BMP2401L2M1.JPG

--Bill

I like this view because it has the horizon (almost) horizontal. This is in spite of the rover being on a hillside. I presume the surface is quite bumpy and here we are luckily levelled by one of the bumps. Solander point has appeared on recent images as if it were a considerable hill, whereas like Cape York it is more like a shelf on a sloping surface. The top of it is about ten metres above plains outside the crater, useful perhaps for spotting distant horizons but not really much of a hill.
http://qt.exploratorium.edu/mars/opportuni...BMP0702L0M1.JPG

For what it's worth: a short traverse sequence from Sol 3356.

Click to view attachment

That's great! I always like driving gifs.

Phil

Bit of a salutary lesson there when making assumptions from orbital images. Remember the DEMS of Cape York which had it looming over the neighbourhood?

There's some real parallax going on with with Solander Point and the distant ridge behind it, as I suspected a week or so back. It's quite clear now. We're getting so close to our winter hangout!

Click to view attachment

Having recently reviewed imagery of the approach to Cape York, I was reminded of the puzzlement of how low the relief of CY was from the Meridiani side. Of course this low relief was emphasized by a tricky optical illusion with the HiRISE imagery-- with the prevailing wind from the East, the Eastern side of CY tends to have the light-toned fines removed, leaving the dark-toned fragments behind, and then depositing the light-toned fines in the wind-shadow on the Western slope, thus giving a false emphasis to the apparent relief of CY.

At least Solander and Tribulation have some relief...

--Bill

I didn't think it was possible, but you're clearly right. I estimate we're around 800-900 metres from that visible upper edge of Solander, which translates into a parallax of about 1.5 pixels at pancam L/R separation against the far background. Nice job spotting that!

A.J.S. Rayl's new Planetary Society monthly update on Oppy is online.

http://www.planetary.org/explore/space-top...nder-point.html

Here is the Sol-3355 drive direction 3x1 Pancam, cropped and reprojected in a polar format. This was cropped to show the fore- and mid-ground. It is oriented in the drive direction, with South approximately up. Note the wonderful texture of the outcrop, especially in the foreground.

--Bill

Wow, Oppy's 10 year launch anniversary is coming up! IIRC the launch date slipped a couple of times and there were suggestions that if it was pushed forward much further it could have to wait until the '05 opportunity.

An intriguing and tantalising snippit:

Here is the Sol-3356 drive direction 3x1 Pancam, cropped and reprojected in a polar format. This was cropped to show the fore- and mid-ground. It is oriented in the drive direction, with South approximately up. Note the wonderful texture of the outcrop in the foreground and midground, and the bedding in the midground.

--Bill

It would be nice to know whether Tawny was targeted or happenstance. Actually it looks kind of interesting. Rounded, sorted grains, texture reminiscent of lower Overgaard and a change from most of the laminated sedimentary surface. Pity in a way that priorities and winter deadlines have precluded any in depth investigation of the approach to Cape York or Botany Bay since a high water table at the top of the mound would imply at least some level of surface flow could have been expected in Botany Bay. Anyway, with the Solander slope hopefully Opportunity will be able to do a bit of roaming and investigation this winter.

The MI that came down today was not "Tawny". Today's MI is p2935 and the named site is p2530. Good sleuthing, though. And a good description of the victim.

As far as I've been able to prognosticate, this MI was taken after the FHazcam IDD check subframe made on Sol-3551 at Site-175/0589. The MI was made on Sol-3552 and is of the corner of one of the ubiquitous flatrocks of the area. This, AFAIK, was made after the IDD arm went C R E A K and they did a diagnostic on the spot.

Attached is a location image with some enhancement. This rock, which I am informally naming Ferd, was a surprise to me. It is more coarsely clastic than I would have expected. But this is a completely different area (and era) that what we have studied before, so it certainly falls within my expectations. I wish we had a better understanding of the Meridiani Onlap.

Anyway, this MI of today is the first of a series p'haps 20 MIs to look forward to.

--Bill



NOTE: Serpens was right, this site is "Tawny". Corrections and apologies made...

No - the MI and the fhaz subframe are indeed "Tawny". p2935 isn't a site code, it's a command sequence number.

(For reference, the Pancam images of Tawny were taken on sol 3353 at site 175/0591, after backing up from site 175/0589 where the arm work was done. The image ids for the Pancam images are 1P425857332ETHC3NNP2530L2M1 through 1P425857701ETHC3NNP2530R7M1; the site code is 'C3NN'; C3 = 175 and NN = 0591. This will all get much easier once the images actually come down.)

Correct, and I apologize to Brian for poo-poohing his location ID.

I have gotten into the habit (shortcut ??) of using the command sequence number (an action) to identify a location. I guess I started doing this since I use the Pancam Tracking Database to keep track of what, where and when was done. This works most of the time, but sometimes doesn't.

Ferd is now known as "Tawny".

And we do have a Phobos image upcoming:
03359 p2739.01 0 0 0 0 0 0 pancam_phobos_deimos_prepoint_L1R4

--Bill

More Phobos and Deimos imagery & another southward drive due on 3360.

Check out "Latest Images", new MIs of "Tawny" as well as a stereo pair of "Lake Eyre":

http://www.midnightplanets.com/web/MERB/latestImages.html

Yay.

Here is a cropped x-eyed stereo pair of "Lake Eyre". That is one rotten, weathered rock.

--Bill

Is it my imagination or are the blueberries around Cape York and in Botany Bay more misshapen and elongated than the near perfect spherules from earlier in the mission? While the nice round examples imply a static groundwater environment, more elongated concretions would support groundwater flow. I have always had difficulty reconciling the clear evidence of a long lasting water table at the top of the mound around Victoria, Erebus and Endurance and the hematite concretion signature from the Endeavour crater infill , with the seeming lack of evidence of water flow in the sulphate sandstone around Cape York and Botany Bay. Can anyone point me towards any papers or articles that address or correlate the probable groundwater effects over the area of the traverse?

We've been climbing a bit as we go south - this image looks back at Cape York (mosaic of 2 Navcam images on sol 3354). Below is a roughly x6 vertical stretch. The nearer object is Nobby's Head, with Sutherland Point almost hidden behind it. The farther object is Cape York, with a few dark spots at the left end being rocks at Odyssey crater. Everything tilts in towards Endeavour. Pancams of this area from Solander should be quite impressive.

Phil

Click to view attachment

Serpens, the Berries seen post-Cape York do appear to be differently-shaped, less perfect-spheroidal, but I can't call them "elongated" . But yes, they are different. I've been holding off, awaiting more of the "color clast survey" and "systematic foreground" and MI imagery before looking more closely. I may go ahead and pull together some type examples of the Berries we see on this leg of the Traverse just to get started and finisah up when the data hits the PDS.

Good idea, though. My thoughts are that on low-transmissivity, low gradient aquifers, as we have here, the groundwater velocity will be so exceedingly slow as to preclude streamlined concretions. I don't know of anything in the literature. Maybe Mr Don Burt would know.

Anyways, attached are two Berries cropped from MIs of the site Tawny on Sol 3352. My first thought is that these look etched or corroded.

--Bill

I don't see that, Phil. From the DTM altimetry image of the Western Rim of Endeavour, Cape York is a high point, Solander Point is a high point, and Botany Bay is rather saddle-shaped. On the attached crop of the DTM, CY is near the top, Sutherland and Nobby are two little nubbins and Solander is near the bottom.

--Bill

Oh, OK, I was thinking that because we now had a view back slightly above the plane of the Nobby's Head pavement - my image above shows the pavement looping around the Head, not just projected as a straight line. But that could occur through different geometries, I guess. I was thinking of climbing a bit from just after Nobby, not all the way from Cape York, but I was probably wrong anyway, it's just the way Nobby is tilted, I think.

Nice topo map!

Phil

Yes, a "lookback of where we was" is always of nostalgic interest. I remember one we did just as we departed Erebus Crater, looking back to Endurance over the Purgatorian Sea of Sand.

That map is a quickie "browse" DTM map from http://hirise.lpl.arizona.edu/dtm/dtm.php?ID=ESP_018701_1775 . The really nice .JP2 HiVIEW images have 600MB filesizes, much to much for me on Dialup. I need to go to our Public hi-speed 'Net connection at the Library with a Thumbdrive and do some DTM shopping. I'm sure that the .JP2 has "scalable" elevation scaling so one can get better resolution for a specific area. A contour map would be spiffy.

Maybe one of our local DTM mavens can work something up. Ditto on the upcoming project are at Solander.
/hint

--Bill



ps-- and in the FWIW dept:

03360 p2740.01 0 0 0 0 0 0 pancam_phobos_deimos_L1

for tomorrow.

--b

There is a nice contoured perspective view on p.51 of this PDF:
http://www.google.co.uk/url?sa=t&rct=j...d2k&cad=rja

Nice. I knew bits-and-pieces of how-we-did-it, and this thesis is a good summary of all that.

Ah, to have access to GIS and DTM software and databases...

--Bill

And here is a mosaic of Tawny, the MI target of Sol 3352. Not a great job, there are always problems with mixed shadows
and full sunlight.

--Bill