Well, with Oppy on solid ground now I think we can say she has officially arrived at the Etched terrain.

On a side note, is it my imagination, or is the dust in the air clearing a lot the past few days? I haven't seen a shot this clear in ages...or perhaps this etched terrain is on slightly higher ground than the surround sea of dunes?

http://marsrovers.jpl.nasa.gov/gallery/all...47P0607L0M1.JPG

Oppy should be able to traverse more quickly over this rocky ground. Is Victoria peeking up from the horizon ?

> Oppy should be able to traverse more quickly over this rocky ground.

Yes, but see that there are more sandy terrain until we reach Erebus.

> Is Victoria peeking up from the horizon ?

As already said before, Victoria is below the current line of sight.
It won't be visible until a point more or less at the half-way between Erebus and Victoria.

I see that around there, etched terrain, there are more outcrop than the north way from the Endurance crater. The question is why it is so?

1) The land is higher than the north?

2) This zone has stronger or more often winds?

3) The water started to flow first around Erebus?

4) "By that time there were more Roman cart traffic?

Rodolfo.

With my opinion Erebus, like Bonneville, is not a major scientific target, as it is filled with sand and probably dangerous to try to descend in. So it is possible that they even not attempt to get closer, taking a short cut through etched terrain toward Victoria. The later is anyway an important target, at it may exhibits a much thicker layer of evaporites than Endurance. So the situation is similar to Endurance, but there may be no way to descend into Victoria, or no way to get out.
At last we are now sure that etched terrain is exposed layers of evaporites.
But with RNeuhaus I wonder why terrains are so different, while sharing the same geological properties (20-40cms of sand on evaporites):
-Near Endurance, flat terrain with only small ripples
-Near Viking, larger dunes
-An now round Victoria-Erebus, dunes separated by troughs hollowed down to the evaporite layer.

Would it be wind channels on Mars? And why?
Maybe the ration sand/blueberries is responsible for the dunes variations? or some component of the evaporites?

Erebus is potentially an important target since it is a deep excavation in the Evaporite sequence which has much of the ejecta weathered and eroded away. We are essentially left with a big road cut: although the interior of Erebus is sand-filled, the walls are visible With Victoria, it is newer and fresher and has a huge ejecta blanket obscuring details.

IMO, a significant target here ought to the "dark basal unit" (D1, D2 and those &%$# dark angular pieces we see) since it is something we didn't see at Endurance.

--Bill

Let's see what the science instruments tell us about the etched terrain outcrop.
It seems the weekend will be spent there :

Bill,

Looking at the map there might be some pretty hefty dune fields between Oppy and those targets (D1, D2). Driving through Erebus itself seems totally out of the question, so how likely is it that we can reach these outcrops? On this side of the crater there doesn't seem to be so much interesting stuff, does it? And how much topography does the etched terrain actually offer? Between this location and Victoria it seems to be as flat as a pancake. Maybe this is enough reason to put the pettle to the metal and try to reach Victoria ASAP?

There may be dune fields, but there is also the evaporite pavement along the north side of Erebus, which might be easily travelled. We'll see what it looks like once we get to Erebus.

--Bill

Bill,


the evaporite pavement near Erebus is already known, and there is no hope to go deeper in Erebus than in Endurance, so I think it is why Erebus is not an important science target.
On the other hand, there is this pavement you mention along the norh side of Erebus, that may be easily traversed. (At rough guess, as it seems that there are many "Anatolia type" pits and cracks in the etched terrain). If they choose this path, they could spare some days to have a look into Erebus.
What makes Victoria very interesting, is that it is much deeper than Endurance, and so deeper layers of evaporite may be exposed, eventually underlying layers of another nature (which seem black in comparison with the evaporites). So They will certainly try to descend into Victoria, even if they could never get out of it. A similar bargain was made when discussing about descending into Endurance.

New PanCam images!
This is the full-res stitch from L2+L7 filters:

And we have a RAT - the first RAT in many months!!!
http://marsrovers.jpl.nasa.gov/gallery/all...47P2573R1M1.JPG

You wouldn't need to go into Victoria crater to examine the deeper layers. After all Victoria is a crater so you could examine the ejecta to measure the same stuff. Ofcourse this wouldn't give you direct information about the depth the stuff came from, but miniTES might help there. Also I think it wouldn't be a big deal if you could get in, but couldn't get out. I guess that other stuff that's different enough from what we've already seen to make it scientifically worthwhile, is probably way too far away to reach it. So going into Victoria and dying there may be very well the right choice.

Yikes, some of those dunes look pretty darn big.

Loads of exposed rock all over the place here too. Hopefully the wind will have granted us safe passage between the dunes. I too would like to see Victoria. I wonder how many Pancam shots it'd take to get a rim-based panorama of that.

The same number of shots that it would take to get a panorama of anything else.