Excellent work !

The 2007 view in particular is phantastic (one of the best meridiani vistas so far)

Oh, but the undulating tracks in "2006".... - Lovely! She's really chugging along over the waves like a little fishing-boat off the Grand Banks!

Oppy's tracks in those (superb) mosaics really look like driving ontop of very wet sand... or wet clay

Good job. I tried that one with autostitch but the results were only regular.
One comment / correction: That mosaic was taken "mid-drive" during sol 2011 and the crater is not Nereus but actually Nautilus. A similar mosaic was also shot at the same position but with the pancam.

02011::p1713::03::6::0::0::6::0::12::navcam_3x1_az_198_3_bpp
02011::p2411::20::36::0::0::36::2::74::pancam_Nautilus_9x1_L257R2

Thanks for all the nice comments. Here is a quick go at the sol 2011 drive direction mosaic.



James

Agreed and a good observation. As has been noted previously, the apparent particle cohesion is most likely caused by a high content of salts that have sucked enough moisture out of their environment to render them sticky. Low temperatures favor the accumulation of moisture by hygroscopic or deliquescent salts. Wicking and evaporation of condensed moisture towards the surface could increase the salt content there (the duricrust hypothesis that dates from Viking lander days). The surface looks "wet" when it is actually salty, cold, and just a tiny bit moist (owing to the salts). Or at least that's one explanation.

-- HDP Don

Actually the tracks don't look significantly different to the Apollo rover tracks.

Any stickiness would result in the wheels getting thickly coated with the damp regolith. It would be apparent immediately, and would have become a major problem from sol 1 on. The tracks look much more like impressions in fine dry powder - like lunar tracks as serpens said. But it's the behavior of the dust on the wheels that clinch it - it cakes on and then falls off, it doesn't really stick.

Phil

Today, sol 2014, was once again dedicated for driving. About 60m were added to the odometer.
Here's a snapshot from Google Mars with our current position, based only in the mobility data while today's images don't hit the exploratorium. Opportunity is about 100m (two driving sols) from reaching a very big patch of bedrock which will probably be our "yellow brick road" for the next month or so.
Check the KML file in the route map thread and don't forget to download SFJCody's map extensions to see the background map to the west.
Click to view attachment

Edit: added a link to the map extensions.

Phil and Serpens - Thanks for your insights. Your logic apears excellent, although "damp" might be completely the wrong word here (i.e., for a molecule-scale coating of polar water molecules on top of unsatisfied ionic bonds), and weak self-adhesion of dust particles, allowing the development of "wet-appearing" vertical walls in ruts, isn't the same as strong bulk adhesion to a vibrating foreign object such as a moving wheel. Utter lack of personal experience dealing with martian conditions (very fine cold heterogeneous salty dust in a near vacuum in a weak gravity field) may have led me, and possibly you also, astray. Terrestrial experience (thick, moist, warm atmosphere, little day-night temperature difference, clay-dominated dust particles or rounded quartz sand, few salts, strong gravity field) could be misleading in dealing with Martian conditions. Lunar experience (perfect vacuum; hot dry angular salt-free glassy agglutinate particles) could also be misleading in this regard.

Bottom line: I don't know who is right, possibly none of us, but I'd be wary of either terrestrial or lunar analogs.

-- HDP Don

The circled crater looks young. Perhaps it will be the next stop.
Click to view attachment

Yeah, I think you are right.

Speaking of craters, I saw that today's imaging plan has a sequence to take a pancam shot of a crater named "Gjoa". I believe it is this tiny little crater right beside the rover's position on sol 2014.
Click to view attachment

After searching for its meaning I found this: http://en.wikipedia.org/wiki/Gjøa.
"Gjøa was the first vessel to transit the Northwest Passage. With a crew of six, Roald Amundsen traversed the passage in a three year journey, finishing in 1906."
Really nice name selection, isn't it?

Block Island was visible in a HIRise photo. Large slabs of bedrock are often visible on HIRise photos. However, the only distinct rock that I remember seeing on the open plains was Block Island. What I wondered is whether all distinct visible rocks on the open plains in HIRise photos are meteorites?

I wonder whether it would be worth searching for similar distinct rocks on HIRise photos over Oppy's entire projected route to Endeavour Crater?

If we found such a rock then we could suggest a deviations of a few 100m to the left or the right to investigate that promising looking rock.

I see 3 dimples in this shot. I am guessing those are tiny craters. I would like to the them look at one with the Microscopic Imager.

Source

Bang my head moment here, but in my view from Google Mars the HIRISE image ends before this point Alan. Did you do your own overlay? OR am I doing something wrong here?

http://www.unmannedspaceflight.com/index.p...st&p=142132



EDIT:
Oops, Thanks Tesheiner (below) for correcting the link (now fixed)
I was being lazy and just copied what was in my browser rather than clicking on the post number to get the link. As I have the the board set to display 40 posts per page it wouldn't have worked for those set to only show 10 per page.

James, thanks for finding the post but the link above points to two pages before, at least on my browser. This one goes directly to it: http://www.unmannedspaceflight.com/index.p...st&p=142132

(BTW, I should better add the link to my previous post on this thread.)

It might be worth equipping future rovers with an instrument for accurately dating meteorites from their isotope ratios. If meteorites are common on the Martian surface, that might serve to constrain the age of the terrain and the rate of erosion. Perhaps an enhanced version of the APXS could have that capability.

Thanks James. I knew it had to be something like that.

What is the scale on that image: how big is Gjoa?

Looks to be about 4m across.

It's partially visible on this image: http://qt.exploratorium.edu/mars/opportuni...U9P1861L0M1.JPG

Now, it's 70m behind the current position.

We're almost 500m west of Block Island already.

Indeed, at this pace, we could be at Endeavour in a year and a half (or so, I'm not claiming precise arithmetic here). Wishful thinking, perhaps, but I am loving the current commitment to drive, drive, drive. Keeping my fingers crossed that they have truly figured out the key to keeping the RF wheel happy without delaying rest stops.

It'll become even better for RF in a few more meters when we'll hit the hard ground

Let's see if we have any hint of information about the currents in the next official status report.
Meanwhile, just say that I believe Opportunity will stop here for the weekend; there are some MIs planned for tosol so guess the next move may be on saturday or sunday.

From the current status report:

Here's the navcam mosaic taken during sol 2017 and pointing towards SW.
Click to view attachment

New intersting rock ahead ? After the next drive, we will not be very far. The rock is near the horizon at right on this navcam.

http://qt.exploratorium.edu/mars/opportuni...23P0733L0M1.JPG

Waiting for pancam.

Does anyone have any thoughts about the curious Microscopic Imager images that came down from sol 2016? A front Hazcam image from the same sol shows the dusty MI pointed toward what I am guessing is the shoulder elevation actuator of the IDD. I am not sure that is what it is, but it's my best guess after comparing the images to a drawing and a model of the rover.

I wonder what they may be looking for.

Yes, interesting....????
Click to view attachment

Problem? Pointing error? Test for Spirit's "Matrix-move"? Hmmm?
Maybe they're thinking about Doug's suggested MI self-portrait.

I few more small mosaics. Drive directions from sols 2013, 2014 & 2015 and Gjøa Crater.

All the thumbs link to the same blog entry.

2013


2014


2015


Gjøa Crater


James

Rubble pile up ahead (is that what you meant Bill?), with another possible BI beyond it..?

Click to view attachment

Mmm, this rubble pile is exactly on our way. Guess we'll do a little pit stop there. My 2c.

Gjøa Crater (what a strange name… Scandinavian for sure, no?) on Sol 2015 :


Navcam panorama of Sol 2017 :

The wise guy who put electrical tape over the instrument!

...which of course leads to the question I've been afraid to ask, to wit: What the hell IS that thing? Been assuming that it's part of the descent stage release mechanism or some other such system that's long since fulfilled its purpose.

It looks to me like the shoulder altitude drive based on:

1) It is covered in tape (so that limits it to Kapton? covered yellow/brown objects)
2) The geometry - I think that is the base of the IDD shoulder support in the background, looking at it from slightly below.

So I think it is the horizontal brown cylinder that is just left of center in:



Airbag

Yes this one. Attractive isn't it ? New heaven's gift or classic ejecta from the nearby crater ?
Next stop we will know (if we stop!).

Gjøa was the name of the ship that Norwegian explorer Roald Amundsen used to make the first voyage through the fabled Northwest Passage in the Canadian far north. There's still a town named after it up there where he wintered, 'Gjoa Haven'. A few years later he led the first successful expedition to the South Pole. So in short, it's named after a ship of discovery.

Back to our scheduled programming...

Ah. Thanks, Airbag; that looks like a pretty good candidate!

It looks like we sailed past the rubble pile on sol 2020:
http://qt.exploratorium.edu/mars/opportuni...23P1201L0M1.JPG
but the rock still could be a target:
http://qt.exploratorium.edu/mars/opportuni...00P0753L0M1.JPG
It's certainly reminiscent of BI:
http://marsrovers.jpl.nasa.gov/gallery/all...00P1985R0M1.JPG
but we'll need closer pancam views before we can utter the "M" word again...

Hmmm... it's a meteormight...

That's an interesting big dark area up on top. Mebbe a big 'ol cavity?

Sure looks like another Block Island...
Click to view attachment

Wait a minute! That is Block Island...we've been going around in circles!!!!
OR maybe it's following us

Pancams are down:
http://qt.exploratorium.edu/mars/opportuni...00P2418R1M1.JPG
I think we're starting to see cavities... Anyone able to spot it on the full-res hirise images? It does look somewhat smaller than BI.

Click to view attachment

The plot thickens, much like fusion crust on the right....?

I processed the 'block'...and it looks like a RHINO

The cavities, etc. scream iron meteorite, but we shall see!

Click to view attachment

cheers

Oh no - this better not be another interesting rock, I want to drive!

Phil