Mars Rover Spirit Mission Update Thread

[thechemist]

Don't be in such a hurry...<br />Spirit is having some trouble with soft sand, just like Oppy after Wopmay.<br />Let's tackle them first, hopefully soon.<br /><br />Forward HazCam image <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[fangsheath]

Spirit is having a lot of difficulty on this slope, but man is she gaining some elevation. We can almost see the horizon beyond Clark Hill now.

 

[fangsheath]

Spirit has backed down the slope considerably and pulled up to this curious little outcrop. I imagine there must be something fairly provocative about it to make them reverse course like this. Perhaps some Mini-TES result gave them pause.

 

[fangsheath]

In false color this outcrop does appear rather different from what we have seen before. Texturally it is somewhat reminiscent of Peace and other similar rocks, but the parts of it that are not completely dust-covered appear very light, which suggests to me that it is perhaps even more packed with sulfates. As we get deeper into the Columbia Hills I think we are seeing more and more formations that at one time were saturated with water. I am anxious to hear an analysis.

 

[chris_in_space]

Why in "false colors"? How would this picture then look in real colors?<br />

 

[centsworth_II]

The following is how I understand it, although I don't do any image processing myself:<br /><br />It may not be possible to see the image in real colors, if the required filters were not used in taking it. Quite often, rather than using the red filter that would give a more true color, the scientists use an infrared filter that gives them more information about the composition of the rocks, but less information about how the rock would look to the human eye. Someone processing the image can add the missing red to get an approximation of what a color image would look like.<br /><br />Even when an image is available with the proper red filter used, calibration and exposure information must be available and taken into account when combining the images taken with different filters to get a color image. In other words, it ain't easy. On the other hand, the "false color" Mars images are probably every bit as realistic, in general, as the snapshots found in family photo albums. <div class="Discussion_UserSignature"> </div>

 

[chris_in_space]

So you suggest that this picture was taken using the infrared filter and that's why it is labeled as having false colors?<br /><br />Because I think it's the opposite. For me this image was taken using the red filter and NOT the infrared one.

 

[centsworth_II]

I don't know the specifics of that particular image. It's also possible that "false color" could be used differently by different sources to reflect different shortcomings in the information used to produce the image or different types of artificial enhancement. Or simply the fact that no calibration information was available. I don't really know if there is one specific definition of "false color" as it relates to the MER images. <div class="Discussion_UserSignature"> </div>

 

[spacechump]

It may look a little more like this but still do believe that probably the L2 or L3 filter was used instead of the L4 (red) filter. The dead give away is the blue color of the rock that even after processing is still pretty blue. In "approximate true color" that rock would probably appear more grayish in color.<br /><br />

 

[fangsheath]

My composite was made with images taken through the 432 nm (violet), 535 nm (green), and 753 nm (infrared) filters. The images were used as is, without correction. The only processing I did was to lower the brightness and increase the contrast a bit on the final image. <br /><br />"True" color is a tricky concept. The reason I call this image "false" is that it is uncorrected. I would use the same term even if it had been made entirely with visible light images.

 

[Swampcat]

Check out this post to see my "approximate true color" version of this image. It actually uses the infrared, green and ultraviolet filters so, technically, it might be incorrect to call this "approximate true color." However, I have seen other images using these filters posted by JPL that are also called "approximate true color." I suppose if it's good enough for JPL it's good enough for me <img src="/images/icons/smile.gif" />.<br /><br />It's my understanding that, without color correction, an RGB composite would be called "false color" irregardless of the filters used. The term "true color" would be reserved for images using the red, green and blue filters with appropriate color adjustments.<br /><br />Caveat: As I've said before on this board (and centsworth_II noted), it is very difficult, if not impossible, to get a "true color" image with the data that is available to the public. I make no claim that my images reflect reality. The color adjustments I make are largely based on my study of color images produced by JPL plus lots of trial and error to duplicate their color renditions.<br /> <div class="Discussion_UserSignature"> <font size="3" color="#ff9900"><p><font size="1" color="#993300"><strong><em>------------------------------------------------------------------- </em></strong></font></p><p><font size="1" color="#993300"><strong><em>"I hold it that a little rebellion now and then is a good thing, and as necessary in the political world as storms in the physical. Unsuccessful rebellions, indeed, generally establish the encroachments on the rights of the people which have produced them. An observation of this truth should render honest republican governors so mild in their punishment of rebellions as not to discourage them too much. It is a medicine necessary for the sound health of government."</em></strong></font></p><p><font size="1" color="#993300"><strong>Thomas Jefferson</strong></font></p></font> </div>

 

[Leovinus]

That link doesn't work if folks like me don't have your same posts/page setting. I run at 30. <div class="Discussion_UserSignature"> </div>

 

[spacechump]

Thanks for the clarification swampcat. Your approximate "approximation" blows my approximate "true color approximation" approximately 12 inches out of the water!<br /><br />Is color correction determined by radiometry readings with regards to the sundial color map?

 

[Swampcat]

<font color="yellow">"That link doesn't work..."</font><br /><br />Yeah, it doesn't work for me either <img src="/images/icons/blush.gif" />. At least it was close <img src="/images/icons/smile.gif" />.<br /><br />My apologies. It was very late in my day when I wrote that post and rushing too much. Anyway, I think I fixed it.<br /><br />Thanks for pointing out my boo-boo <img src="/images/icons/frown.gif" />.<br /> <div class="Discussion_UserSignature"> <font size="3" color="#ff9900"><p><font size="1" color="#993300"><strong><em>------------------------------------------------------------------- </em></strong></font></p><p><font size="1" color="#993300"><strong><em>"I hold it that a little rebellion now and then is a good thing, and as necessary in the political world as storms in the physical. Unsuccessful rebellions, indeed, generally establish the encroachments on the rights of the people which have produced them. An observation of this truth should render honest republican governors so mild in their punishment of rebellions as not to discourage them too much. It is a medicine necessary for the sound health of government."</em></strong></font></p><p><font size="1" color="#993300"><strong>Thomas Jefferson</strong></font></p></font> </div>

 

[Swampcat]

<font color="yellow">"Is color correction determined by radiometry readings with regards to the sundial color map?"</font><br /><br />Huh? Gee, a technical question...now what do I do?<br /><br />Actually, I studied the color calibration wheel images early on in my efforts to understand how to produce color images, but for the most part I relied on trial and error comparisons with JPL's color images while manipulating brightness, contrast and saturation -- a strictly empirical approach. Maybe someone out there with a better understanding of how JPL processes the raw images could give you a good explanation of the proper method for determining color correction since I have only a basic understanding of the process. I'm reasonably certain that the color calibration wheel comes into play. However I couldn't give you any details. Sorry <img src="/images/icons/frown.gif" />. <div class="Discussion_UserSignature"> <font size="3" color="#ff9900"><p><font size="1" color="#993300"><strong><em>------------------------------------------------------------------- </em></strong></font></p><p><font size="1" color="#993300"><strong><em>"I hold it that a little rebellion now and then is a good thing, and as necessary in the political world as storms in the physical. Unsuccessful rebellions, indeed, generally establish the encroachments on the rights of the people which have produced them. An observation of this truth should render honest republican governors so mild in their punishment of rebellions as not to discourage them too much. It is a medicine necessary for the sound health of government."</em></strong></font></p><p><font size="1" color="#993300"><strong>Thomas Jefferson</strong></font></p></font> </div>

 

[thechemist]

A bunch of very nice route maps have been posted on JPL for Spirit.<br />Plus, an image depicting the next science target : Next Stop: 'Methuselah' <br />A nicely layered rock. Methuselah was the grandfather of Noah, who was connected with a certain flood <img src="/images/icons/wink.gif" /> A hint ? <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[mikehoward]

Also, "Methuselah" has become a general term for someone who is very old. It certainly wouldn't surprise me if this is the oldest layer of rock we've seen yet at Gusev. Discalimer: I am not a geologist. Never the less, this could be very exciting!

 

[fangsheath]

The Methuselah area does have some interesting layering, including some of the most obvious cross-bedding I have yet seen in the Columbia Hills. The rover is presently to the left of this frame.

 

[centsworth_II]

I'm not generally one to spot artificial structures in the MER images, but that does look like a well constructed tunnel entrance for mini Mars buggies at the far right of your Methuselah image.<img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> </div>

 

[rogers_buck]

Don't be silly. That is just the shadow of the heat ray stalk of a martian war machine. Tch, some people. (-;

 

[thechemist]

Alive Dust Devil movies in full resolution from JPL<br /><br />Click that link even if you have to beg for it <img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[thechemist]

Don't just stand here watching this isolated frame. Go at the JPL site and download the animations ! <div class="Discussion_UserSignature"> <em>I feel better than James Brown.</em> </div>

 

[Leovinus]

link to animation <div class="Discussion_UserSignature"> </div>

 

[abq_farside]

That was too cool <img src="/images/icons/cool.gif" />! <br />Thanks for the link. <div class="Discussion_UserSignature"> <p> </p><p><em><font size="1" color="#000080">Don't let who you are keep you from becoming who you want to be!</font></em></p> </div>

 

[telfrow]

Am I seeing things or are there two shown in that animation? The one in the foreground, moving from left to right...but there seems to be one just beginning to form in the distance (It's near the starting position of the one in the foreground, about halfway to the horizon.) Does anyone else see it? Or is it my eyes? <div class="Discussion_UserSignature"> <strong><font color="#3366ff">Made weak by time and fate, but strong in will to strive, to seek, to find and not to yeild.</font> - <font color="#3366ff"><em>Tennyson</em></font></strong> </div>