New Mars Forums

i think he was referring to http://www.lyle.org/mars/imagery/1P1378 … .html]this image or http://www.lyle.org/mars/bysol/1-109.html]others like it from sol 109
IMHO, i think the "pillar of light" is just a reflection off the inside of the camera lens or housing (the camera does happen to be pointing directly into the sun, so there should be lots of flares and other lens artifacts depending on the camera angles), the images with the vertical line pointing UP as oppsed to down, are quite odd.  Also, note that you can see the pillar of light superimposed over the ground also. If it were truly an atmospheric phenomenon (such as a sundog type of effect) then it would only be seen in areas of the sky. speaking of sundogs, im sure they exist on mars and the rover should be able to get some good images if we get lucky, but i dont think this is anything like that. Sundogs are most usually seen at angles that are horizontal to the atmospheric horizon, not vertical.

i cant find that pseudocolor image of the ring around the sun, though.

Its a given that pixel bleed due to oversaturation of the ccd occurs and usually it manifests in things like streaks and blotches like as on the heatshield and on metal parts of the rover when they are in the pictures or even on http://www.lyle.org/mars/imagery/2P1356 … l]features in the rocks (was that a glint from a crystal facet? i still want to know).

Having it mask out in a subtle way a signifficant portion of the terrain horizon is a bit more interesting. As can be seen in http://www.lyle.org/~markoff/processed/ … 1.JPG]this color composite of the area in question, the most-removed areas do correspond to areas with more sky in them, leading to greater oversaturation bleed in these areas. Its not a very consistent effect, but i think its true that this is the cause of this phenomenon.

Its likely that this problem is widespread and we just havent noticed this much before since you need a sequence such as this to see it in context. If this oversaturation problem really happens this easily in only certain filters, then we should be able to go back and see lots of these paticular filter images with extreme bleedover like this (http://www.lyle.org/mars/imagery/1P137167255ESF2019P2566L7M1.JPG.html]heres an extreme example), provided the sky is a small part of the image, especially at Meridiani where the contrast between the dark soil and the sky is so extreme, so any image with a thin section of sky has been compromised, especially when, like this image, it has a dark crater interior you want to get a good exposure of.  So that must be whats going on. I dont think NASA has any motive to doctor the images like this.

On the side, why is it that these images are in the aspect ratio they are? they have apparently tried to crop off as much sky as possible to get better contrast of the ground before making the exposure, but also resulting this oversaturation problem for certai filters due to the fact that a small portion of the sky also made it into the images?

As for the SKY KOLOR, they should fill in a "true" Mars sky color based on the composite data from the time the photos are taken, and this is likely to be a range of colors, which of course are compromised due to the above ccd limitation principle. The only source photos we should make composites from to guage sky color (at least to get an accurate idea of the true color of the Martian sky at that timeframe) should be those images that ONLY include sky in them (ok maybe a little ground is ok), since based on the same principle, the true color value of the sky per each filter shot is compromised by the values in the ground effecting how light or dark the sky gets recorded in the resultant exposure for each filter shot (if the sky gets pegged to 255 in one filter due to this ground/sky contrast scenario and another filter doesnt result in a pegged-out sky, then the sky color is compromised). Due to these spectral differences, the ccd guages the sky vs ground values separately for each of the separate filter shots which ends up skewing the resultant composite towards some inaccurate color. There seems no way to compensate for this unless you take the contrast-skewing effects of the ground per each filter shot completely out of the picture and obtain even exposures of the sky.

Gee whiz, I wouldnt have expected such *glaring* limitations with the ccd. This pretty much constitutes a good case-study of the limitations of the dynamic range of these ccd sensors and how much compromised the data is from these sensors due to this effect (as well as compression artifacts among other things (im waiting for the day when they can make a ccd with infinite dynamic range by merely doing photon counts)). I thought we could do much better than this with 21st century technology but i guess not, these are probably the best sensors we have for all the extreme conditions the MERs need to address...

btw, what is "tin-foil grabbing" ?

it does indeed look like some minor washout debris curtain at the bottom of the channels but we need a closer look to be sure of the
nature of it. From this far away its hard to tell if its not just debris built up through waterless erosion being the blueberries and pebbles
carving the channels instead of water. The dark stuff in the channels might just be blueberries instead of stains or mineralization
deposited by water. Also, from this perspective its hard to tell if the channels were originally cracks that got weathered or if
they originated as erosion carved channels...

I gotta say, i appreciate musing over Cassioli's prolific animations, images and interpretations, all bazillion of em! more power to ya Luca!

now only if all his links worked, some work but some are dead 404s or bring up a generic altervista catchpan page....
for instance the latest ones, http://jumpjack.altervista.org/immagini … zoom-1.gif and http://jumpjack.altervista.org/immagini … es.avi]the avi -wha happen? ???

...by the way what software do you use to edit all those images together and animate them?

I dont know why NASA's Mars program doesn't reuse the technologies that have been developed at such enormous cost. Sure its a good idea to always be developing new technologies for the general vector of progress and thats what NASA does very well, however, I imagine that they could resend a slightly revised MER platform each and every launch window, that way we'd be assured of some public-relations bolstering media coverage that only seems to come from surface missions. The next scheduled lander is the Pheonix 2007 which is based on the failed MPL platform and cant do any roving. The MSL in 2009 is a billion-dollar lander, all NASA's eggs are in one basket here using unproven and highly risky landing technology. Dont get me wrong i think if MSL works it will be money and risk well spent and will make the MERs look like toy missions. I just hope they will refine the design and send another the next launch window after that rather than just sit on it. I think we need lots of inexpensive rovers on Mars to examine lots of areas in a consistent schedule, not just one expensive rover constrained in a few hundred mile area for a few years. Redundancy and pervasiveness is key to Mars exploration and more rovers at a lower cost each seems the only way to do this within a tight budget to ensure the likelihood of success.

Since all the development costs have been already spent on the MER platform, and the technology has been proven and the operations debugged and refined in real-world use, I think they should spend the money concentrating on fitting new science packages into the existing platform (and also increase its roving speed a bit while theyre at it!). I guess we'd need a complete bean-counting to see if the savings really add up, but consider how many years were spent developing the Athena platform, now that we have it perfected lets get our money's worth out of it until the model is obsolete. With a fixed budget this means less money going to engineering new EDL and roving platforms themselves and more of it going to science being done on Mars surface. Im all for the Mars science.

Those Blueberries
...They stay atop the sand and dust due to saltation and low-density...

I'm not an expert of Saltation, but couldnd't you also suppose that the blueberries stay atop the sand and dust merely because the dust is being removed from beneath them by wind action? There probably isnt much soil sorting going on here. Any sand grains or dust next to a blueberry just gets blown away, but the blueberries remain. You might have some sand dunes covering over blueberry fields from time to time as they migreate, but generally the blueberries slow dust removal by acting like desert pavement, they stay at the top merely because everything else blows away, otherwise there should be lots of dust being kicked around in this area.

Closely related question: Are wind measurements being taken by the rovers? I haven't heard a peep about this...

The leading theory is that the "gullies" are NOT formed by springs (that was the first hypothesis back in 2000 using MGS data (the "ice-dam" idea), the problem with this was that the "springs" come from high up in the crater walls, and there is no chance of a water table being this high)

The most likely hypothesis (using Oddyssey data from a couple years ago) is that the gullies are formed under a blanket of snow which is in turn underneath a blanket of dust (this snow theoretically still exists to this day right next to areas where it is all evaporated away and has revealed the gullies to us. the areas where snow still exists correspond to areas of less sunlight so it fits all the observations). So the sun slowly warms the snowpak, protecting the water beneath it from freezing, this allows it to melt and run down the slope under cover of the snowpack and carry debris away forming the gullies. Eventually the snowpack melts/evaporates away and reveals the gullies to the sky.

i used to think it might be a dust puddle, but why does this one look so different from the other ones? the other ones being the flat rock tops at the bottom of the divets in a lot of places between Eagle and here. the flatness coming from the wind eroding the bedrock chunk which leaves a vacancy left except for the few blueberrries that fall out of it and dont blow away. the other blueberries form a slope down to this vanishing point remnant of an eroding crater ejecta fragment. but this one is too smooth and anomalously flat

if it were water that would imply a water table very close to the surface and there shoudl be more evidence of such everywhere like in the crater bottoms and other low points, perhaps the ice-dune sculptures in the bottom of Endurance crater are related.

but most likely there lies some alien feature that the shadow government's black ops inside NASA has decided to replace with this compression artifacted and neutralled-out splotch since the world is not ready for the truth yet.

its hard to tell from the picture whether the craters are the source or the destination of the water, as in gusev the crater appears to be the destination.

if the crater were the source of the water, then inded it would apper to have breached an artesian water source. the sinuous channels should lead to some reservoir outside the crater which shoudl be a deep sediment bed like Meridiani.

But i wonder what would happen today on Mars would the water tend to signifficantly evaporate away before it could accumulate into a log-lasting sea or lake? or would it tend to accumulate a cover of ice protecting it from evaporation in the lake and increasing erosion in the channels? but in any case, lots of debris was moved via this channel and so the sediments should be pervasive and we shoudl see evidence of deltas or debris pans leading from this outflow channel (maybe there are some better pics of this area?)

The image shows some sinuous channels, but It seems more likely that the impactors melted the subsurface ice and it flooded out carving the channels.

Artesian wells are often used to describe geysers and natural springs, differentiate this from an artesian *well*, where you actually drill beneath impermiable rock layers to create your own spring (and dont need to install a pump like in a non-artesian well). I think it might better be refered to as a spring or geyser.

However, it got me thinking that the conditions on Mars might be more conducive to artesian wells than they are on Earth. On Earth theres a lot of faults cracking and making plenty of escape routes for water tables to drizzle out as springs in many places tending to lessen the pressure except for a few situations where a slope of impermiable rock overlies a water table on the downward side of this you find artesian wells where there is some faulting. converseley on Mars, there should be a lesser concentration of faulting basically because theres apparently no ongoing tectonic activity, this would tend to make the water table sit higher and the few places where there is a fault would be the sources of artesian wells. On Earth, there are so many faults that mostly all you have are small springs. The problem with Mars is that it doenst rain, so the aqufers arent refilling like they do on Earth, so any artesian wells (or i should say springs) are likely to be ancient exhumed remnants. But if it were raining on Mars then id think we shoudl see many very large geysers at least until they erode out.

...i have always been perplexed by what Fig newtons are, but then they started making all sorts of different flavors and they just call them "Newtons" now. officially, nabisco says theyre "cookies". And then i read a National Geographic article in 1998 with big color pictures about fig wasps and it permanently ruined my appetite for eating anything fig-related. But as an unwitting child of the seventies the commercial of the singing fat guy in the fig suit is irreversibly burned into my brain (even more so than plop-plop-fizz-fizz) and it goes:

ooey gooey rich and chewy inside,
   tender flaky golden cakey outside,
      put the inside in the outside, and its good, darn tootin!
         its the fig-fig newton!
            here's the tricky part, the fig-fig newton!
               one more time! the fig-fig newton!

(sorry to go off tangent in a "Mars" forum, but fig newtons have a very high energy per weight ratio so it could be argued that they might make a good "taste of home" food for settlers morale-support... really, i dont own stock in nabisco or anything, the generic brands were just as tasty)

Thanks, this is truly an incredible image (indeed... planet!). The stems, of which i was so let down when they didnt MI close-up that big one in Eagle, are so much more plentiful here at Fram, now I hope we'll finally get those stem close-ups...

Why so many stems here? because it might be composed of newer debris? Are the stems merely the result of the wind blowing consistently from one precise angle over a long time period eroding everything but the leeward side around each blueberry and leaving these stem supports? In this case all the adjacent blueberry stems should point somewhat parallel, implying the same wind direction...