Changeing lanes:

http://qt.exploratorium.edu/mars/opportuni...BHP1311R0M1.JPG

While the view of Victoris from the rim will be fantastic, and there is real science to do if we can get down into the rocks just below the rim where there's "ramps" into the crater (one may be on the northwest), I think the entire interior of Victoria below the upper rim is a sand trap like the deeper interior of Endurance. Be nice if we could, but don't expect to go there, unless it's a fatal booboo.

What I'm most interested in at the Erebus/Victoria range is exploring the XY two dimensional structure of what I assume are evaporite rocks exposed in the etched terrain. We explored the Z dimension in Eagle and the walls of Endurance, but we need to see it layed out in front of us, stripped of -- it looks like up to 2/3rds -- of the overlying sand sheet we're treking across now. We will see small craters in the rock's surface, not in sand with ejected rock, see the erosional degradation cycle of craters, see fissures and fracture patterns in the rock...... and most importantly, have a real chance of seeing shoreline processes and sub-aqueas sedimentary process laid out in their horizontal geometry.

And if little-green-men walked the shores of this salty acid sea, we'll find their footprints, complete with acid-raised blister marks! <grin>

I hope for the same. There's one "but": we don't *know* if it is rock. It might be a lighter toned, eroded remnant (soil) material of what once was an outcrop of a crater rim....

We'll soon find out, because oppy's driving like crazy again in lines as straight as a ruler. I wonder how they manage to do this with a 7 degrees off axis front wheel

There's one "but": we don't *know* if it is rock. It might be a lighter toned, eroded remnant (soil) material of what once was an outcrop of a crater rim....

AMEN. I'd be very surprised if it was... The highest rez images show all sorts of textures that look like a stripped, eroded bedrock surface, with little spots I'm pretty sure are more and less degraded small impact craters and other fascinating textures at the limit of visibility...

BUT.. it could be... or... "None of the Above"... fossil mats of martian algae?.. I doubt it.. but etched terrain might be a place to look.

I hope I'm wrong, but the 'etched terrain' looks like an area full of very rough rock, not unlike 'karst'.
Also, we should not underestimate the distance between Erebus crater and Victoria crater: over a mile long. And if Oppy reaches Victoria, climbing the crater's rim will be quite a challenge, too.

http://i12.photobucket.com/albums/a250/Moo...hed_terrain.jpg

Where abouts is Opportunity on that map now that they've started driving again?

The red dot in the upper right hand corner

hmmm...are you sure? I would have thought they would have moved further south than that by now.

"I hope I'm wrong, but the 'etched terrain' looks like an area full of very rough rock, not unlike 'karst'. "

It does look rough, but remember the images we look at have usually been sharpened and very strongly contrast stretched. I think a lot of the roughness is albedo patterning of the wind-and-sand-etched surface, with all the little dips and hollows with a few inches of sand and saltation-rolled blueberries concentrated in them.

one of the reasons I'm so obsessed with Victoria Crater is the fact that
this will be the view of a special kind of alien landscape as has never ever been seen bevor ( except the "foretaste" of Endurance)

We have seen other great views, for example from the Columbia Hills across the Gusev Plains: Breathaking ! but at the same time similar to other views we're familiar with e.g. from the Arizona desert here on earth... not the same as on earth of course, but somewhat similar.

Whereas Victoria as a "Rugged kilometer-sized giant crater filled with a bizarre sea of sand dunes" represents a new kind of landscape that is unique to the planet Mars !
We havn't seen something similar on Earth nor on the Moon or any other planet yet.

No, not sure... It's only a general indication of where the rover is/was. She might be much further south already.

Good comments, Ed (et al).

"We'll see what we see when we see it." I hope that you are correct, but in addition to albedo features I see shadows. I hope that the Etched Terrain surface will be passable, but it might be much like the "ghostly ring" craters like Fram and Vostok and Voyager. This is, after all, a "Terra Incognito". Perhaps landing in Purgatory was a blessing, it alerted us to dangers ahead and now we are proceeding with caution and not highballing at breakneck speed (for a Rover, that is).

Once we get to the Etched Terrain proper, there will be plenty of "scratch and sniff" opportunities, in a manner of thinking. Examining the surface of the evaporite unit will be good geology.

--Bill

The contrast between light and dark make it to look like the dark areas are shadows but I think that the light areas in is exposed bedrock and the dark areas soil so it should be very easy for Oppy to drive.

That horizon still looks fairly rugged. My guess is that the terrain between Erebus and Victoria will be somewhere in between 'just drivable' and a maze. Some stuff Opportunity will be able to drive over, elsewhere the rover will need to make painfully circutious routes to make forward progress.

The red dot is about where they got stuck. Opportunity is half way to Erebus from there now.

Phil

A 360 degree panoramic view taken by Opportunity with the L Navcam on Sol 527-528.


jvandriel

...and the previous post (thanks!) reprojected to a polar view.

Phil

Click to view attachment

Phil, Very nice picture. What tool did you employ to strech it out from the top?

Rodolfo

Anyone else think the dunes look as though they are a little smaller now?

http://marsrovers.jpl.nasa.gov/gallery/all...BHP1214L0M1.JPG

Although, it's sometimes hard to tell with hazcam images as they distort objects.

Rodolpho, I did this in Photoshop. The vertical scale change is done by stretching the whole image vertically and then shrinking the foregound in several steps (bottom 80% shrunk 10%, then bottom 70% by 10% (of original height) and so on. I've been told another method with a mask layer could do this but I have never figured it out. This is quick and effective but not accurate, of course, it just gives an impression. Dilo's work with Povray is more precise.

Phil

Sunspot, I have been thinking the same thing: the dunes _do_ look more civilized as we head southward.

--Bill

I think the overall trend in height has certainly been downward since Opportunity has left Purgatory, although it has been variable. Steve Squyres has similarly speculated in a recent update. Each of the camera types do see it differently, and the dunes appear differently from different directions, but I think the trend is real.

Keeping with the nautical theme, let's hope we have left the storms behind us.

Not sure if anyone already posted and, for shure, aren't very last images but...
Click to view attachment
The drive sequence between the dunes is amazing! Great drivers in JPL, maybe Alonso should worry about!

And in the next Sol, they made a "chicane" over a small dune (veery dangerous!)
Click to view attachment

phantastic animations !

Yes, indeed that the front and rear hazcam disorts the images. They are designed for a close up view.

On the other hand, floor is incredibly smooth and compact. Almost no stones except to a small metorite close to heatshield.

Rodolfo

Yes, dilo. It makes a most excellent movie. I also noticed that the downsampled images showed up on the marsrovers site today. There are about 140 images from sol 520 through 523 in the whole thing, and it is quite amazing to watch.

I spent some time trying to make the whole sequence fit into a smaller file for posting, but I gave it up. I have no software that can batch-convert those RGBs into a grey scale, which would have helped reduce the size a lot.

For the MMB users out there, it is command sequence F0006. Just set the time interval between frames to your liking, pick your favorite navcam eye, and launch the slide show. I particularly enjoyed watching an anaglyph version, though you can get a pretty good sense of the topography Opportunity has been traversing from just one of the eyes.

Irfanview does have a batch convert option. Its Advanced options include a 256 color (8bpp) option, but nothing that explicitly says "grayscale." Give it a shot, maybe it'll work. If not, maybe it can be suggested to the author.

Irfanview is an excellent all-around image editor. An 8-bit/pixel image is indeed grayscale. A 24-bit (true color) image is is nothing more than three (RGB) 8-bit datasets combined.

--Bill

Nice animation. Looks like they risked going over a very small dune (pretty safe really) rather than continue into some deeper looking sand. Wise move, I'd say.

Thanks Jeff7, and Bill. It sure looks like it should work, but I tried it and it didn't work for me.

Technically, an 8-bit image can be in color - PNGs use 8 bits per pixel, because each pixel is one of 256 colors in a palette that is unique to each PNG (8 bits can store an integer anywhere in the range of 0-255). Each color in the palette is 24-bit, mind you, but you can only select 256 of them per file..

PNGs have built-in non-lossy compression, so an 8-bit PNG might still look decent while not being too large. By the way, PNGs are similar to GIFs (PNGs are patent-free, is all), so if PNG isn't supported GIF might work.

These days gifs are public domain as well

Unisys's patent ran out in June, 2003.

That's good to hear. I guess GIF is dead by now anyway.. though apparently the patent also applied to just about every file compression format known to man. Thanks for letting me know.

On a side note, Opportunity's deck looks quite dusty.
http://marswatch.astro.cornell.edu/pancam_..._1_True_RAD.jpg
I hope the latest cleaning event was one of several to come.

Nico

Well - a 500 -> 650w hike is substantial

GIFs really shouldn't be used anyway. The LZW algorithm PNGs use is inferior to the LZ77+Huffman algorithm that PNG uses.

The big difference though is in color depth. PNG supports arbitrary bit depths, of course. So you can have a 24-bit truecolor PNG. ...but even at 8-bit it's still better than GIF. PNG supports a 24-bit palette -- GIF only supports an 18-bit palette (262,144 colors). GIF's limitations were basically built around the original IBM VGA card, so the palette limitation is there too.

Gifs are reasonably okay for uncompressed 8-bit black and white, though I usually use compressed TIF's so there's no lookup table at all.

Gifs are still perfectly good for simple unshaded graphicy things like icons or images of text. A gif of a high rez pen-and-ink line drawning can be saved as a 4-bit image and look perfect. Saturated black ink on white background, and partial-pixels on the edges of lines having graytones.

Gifs are also nice as small monochrome animations. If you want big videos, go lossy compression anyway.

Wow, you're right, VGA did only support 6 bits per channel.. I always thought it used all 8. That explains why I didn't get the range I expected when drawing in certain graphics modes, heh. I stand corrected. So yeah, use 8 bit PNG.

Just a polite suggestion guys but this discussion should be in the Imagery & Tech Issues forum.

SOL 536 drive:

http://marsrovers.jpl.nasa.gov/gallery/all...RP1311L0M1.HTML

very good to see her moving slowly but steadily and surely day by day ...
even over the weekend (thanks again to the JPL rover team for the great work and commitment !)

And the best of all: Steve must be a Victoria fan too !!

I was quite a bit reliefed when I read the following passage in Steve Squyres' latest mission update:




this can only mean that Victoria is still considered a target at all (something I must admit I was no longer so sure of after the purgatory event)
ok it will not be easy to reach it, but at least it seems that after Erebus, chances are good that they will actually try the go for the Great Victoria Crater



Nirgal

****=> Opportunity final destination: Victoria Crater by Christmas 2005 !

wrong thread...

Did someone noticed this crater near horizon?
Click to view attachment
I do not know direction, but could be the orange-highlighted in this MOC image...
Click to view attachment

Thats off to the east. I remember seeing it in the panarama they made when Oppy was stuck.

That's because the Erebus map is turned upside down. It took a moment before I realised that too

I hope we visit R2 than D2 first.

yes, Dilo, I think you are probably right about that crater. And look at the horizon beyond it... a view of much more distant terrain beyond a nearby horizon.

Phil

So much for staying in the trenches:

http://marsrovers.jpl.nasa.gov/gallery/all...LRP1605L0M1.JPG

Oppie hopped three dune ridges in one drive, and is running right next to the 'Erubus Highway'

http://marsrovers.jpl.nasa.gov/gallery/all...LRP1605L0M1.JPG

Quick aside here - check out Irfanview again. The PNGOut Plugin with Irfanview has a Gray option for the output type. You might
want to check out the PNGOut tutorial first to try to lighten the compression a bit,
because PNGOut does a REALLY thorough job of compressing files, using multiple passes.


Edit: Well duh, now I see it. Under Advanced Options, on the right side is a checkbox: Convert to Grayscale. None of the messing with the Change Color Depth boxes...geez.
Might that do the trick?

Though using PNG for the rover pics would be awesome - I don't know what it'd do the the filesize, but PNG is lossless. I wonder why NASA doesn't use it? Much smaller files than TIF's.