Imagine prevailing winds for 2,000,000,000 years. Little ridges and furrows in the rock are going to affect the flow of the wind over the ground, causing little disturbances like that I would have thought. The opposite of a wind-tail behind a rock.

Just thinking - perhaps an IDD keep-out volume violation occurred to end the drive early - the bottom of the IDD turret, and the 'end' (nearest to WEB) of the Mossbauer seems quite close to the dune ahead. I'm assuming auto-nav FHAZ pairs are used to establish if the IDD is about to bash into something.

What's good is that whilst the wheels are sinking in a bit to these dunes ( see the RHAZ) - I don't think there's much wheel slippage going on - the cleat marks are neat and evenly spaced.

I was wondering what it would look like if the ground shifted/displaced AFTER dune emplacement.
(The N-S big dunes are remnants from an earlier wind regime.)

Note the subtle little tell on the other side of the dune and how it lines up with the pavement crack running under the dune.
(Inverted image, with gamma correction to bring out details in the "crack" on the far side of the dune)

What I find interesting is that, aside from the localized disturbance in the dune, the dune associated with the upper crack also appears to have a lighter albedo distal of that crack as opposed to the proximal side. That is unexpected (to me). If it is real

Maybe saltating sand is channeled by the crack and piles up right there on the dune sides.

That is what it looks like.

That either means that the dunes are very stable (in geologic time) or that the seismicity is high.

The latter would argue for a seismic mission sometime soon.

Steve M

And the former seems to me to be far more likely around here - apart from meteorite impacts I doubt that there could be any significant seismic activity in this region of Meridiani on any other scale than geologic time scales.

A seismic mission remains one of my own preferred next steps anyway but I wouldn't put Meridiani high on the list of targets.

Not to drift (ta-dah, dah!) too far OT, but does it really matter where we land the first siesmometers in a global net? We have only the vaguest idea of global Martian siesmic activity, and we'd need a primitive net just to localize the current regions of activity.

In this view, Meridiani would be an ideal location for one sensor if for no other reason that the surface conditions are extremely favorable for the terminal phase of EDL.

Lots of Mars seismic network studies have been done over the years, and most of them assume that Tharsis is the most likely generator of seismic events. The most common design of a seismic network is three stations forming a triangle a few thousand km on a side around Tharsis, and one in the antipodal region. The triangle allows probing of the structure around Tharsis, the antipodal station probes the core using signals from the Tharsis area passing through or around the core.

Phil

I am guessing this fault was caused by a meteor impact. Could one side be slumping down? I don’t see much movement either vertical or horizontal.

Think about a landscape being churned up by impactors over the eons. I would think you would get some “air” pockets mixed in. Eventually, the ground would settle, wouldn’t it?

An interesting curved drive over a small dune......testing perhaps for future long long drives ?

The interesting "curved drive over a drift" image that just came down is from back on sol 1774, just before we got to Ranger Crater. It's visible in this QuickTime VR mosaic (3 MB) of sol 1774. Ranger Crater is visible.

Lots of old images being returned currently; few or no new ones. So Oppy is alive but obviously something is up - maybe some temporary communication problem somewhere in the chain, if I were to hazard a guess.

Or just freeing up memory?

Phil

Problem is we never got Navcams of the current position; that's a little worrying. But glitches happen from time to time, I hope it's nothing serious.

<guess mode on>
Perhaps the navcam sequences were not executed once the drive was known as aborted. Since the mid-drive navcams (those taken in visodom mode) were only downlinked today perhaps that's why we don't see any other activity in the plans because those are needed for further analysis. Too many guesses, but the situation is really unusual.

Touching again the point about the "big" increase on the altitude, which MMB represents as a flying rover , now I see that it was a steady and smooth increase during the whole drive and not a false indication due to slippage. In this case, either the terrain as an E-W slope (3.5m change in 80m) or the rover's own calculated attitude has (had) an error and it was propagated on the z axis.
<guess mode off>