True mars color : Myth versus Fact [ UPDATED ] - Page 3

Omicron Persei 8 · #61 (**permalink**) 29-July-2004, 09:22 PM

Quote:

Originally Posted by Bishop

So you anti-green (no organic matter) on Mars guys must be starting to sweat a little huh? Methan and finally some open disclosure on those pesky ESA photos showing green. Sometimes the "establishment" uses conspiracy as a way of buying time: http://www.rednova.com/news/stories/.../story002.html

Try again Bishop.

http://sci.esa.int/science-e/www/obj...objectid=34531

"Note the green colouring is an effect of image processing"

http://www.marsnews.com/articles/200..._in_green.html

And straight from BA itself

http://www.badastronomy.com/bad/misc...reen_mars.html

Irishman · #62 (**permalink**) 29-July-2004, 09:26 PM

Quote:

Originally Posted by Bishop

So you anti-green (no organic matter) ...

Anti-green? If you refer to the pictures, I'm "anti-green" in that I want the images as correctly balanced as possible, and all the evidence shows that bright greens and blues are color balance problems. Regarding life, it would be interesting to find, but the evidence isn't there yet - though the methane and gas traces being investigated are very interesting.

Quote:

... on Mars guys must be starting to sweat a little huh? Methan and finally some open disclosure on those pesky ESA photos showing green.

Sorry, you've been mislead. Your article has the Mars Express image that the Bad Astronomer discusses on his Hoagland pages:

Quote:

The green Mars Express image was not properly color calibrated. The color image was made for a press release, and in general, a spaceprobe imaging team doesn't have much time to put together a pretty image for the press. So they usually hastily assemble something that may not have the colors done perfectly (I have seen this happen more than once). Suspecting this was the case for the Mars Express image, I emailed the Principal Investigator for the camera, Dr. Gerhard Neukum. He kindly replied, telling me this is exactly what happened. [Note added March 12, 2004: in fact, the ESA has corrected the original image so it is no longer green. The new image can be found here.]

In fact, both Don Davis and Dr. Neukum told me that the rocks in the images are basaltic, which are known to be dark grey, or bluish black (the basaltic content was determined using mineralogical image maps made of Mars by spacecraft). This indicates immediately the green color is not correct. In fact, Dr. Neukum told me that the imaging team wants to reprocess the data, but it takes time, and they have a lot of scientific data to go through!

In other words, the green in that image is from bad color processing and is not accurate. Note that the funky pattern is caused by dust devils disturbing the dust on the surface, exposing darker dirt underneath. Thus the streaky pattern.

Your linked article shows the orange and green original bad color image with this caption:

Quote:

Scientists believe the green areas in this image from the Mars Express may be some form of life on the red planet. The X marks the landing spot of the Spirit rover. Image credit: ESA - click to enlarge.

This is wrong. Scientists do not think the green has anything to do with life - as the BA shows above. Scientists know the green is bad color balance and the green looking feature is dust devil trails. Also, the picture has nothing to do with the article in question, about possible microbial life on Mars and especially the possibility of cross contamination from Earth to Mars. Frankly the author of that article is drastically wrong to the point of journalistic incompetence - not that that seems to bother anyone any more. The people in the article make no mention of that image, and if they had been shown that image they probably would have commented differently. In fact, I think I'll try to comment to RedNova about this.

Quote:

Sometimes the "establishment" uses conspiracy as a way of buying time:

Your paranoid delusions are irrelevant. The facts don't support your position one iota.

Edited: I just sent the following email to the RedNova comments email:

Quote:

Whomever selected the picture and caption for the article http://www.rednova.com/news/stories/.../story002.html is so wrong as to be journalistically incompetent. The picture has no relation to the article. The caption is wrong. See http://www.badastronomy.com/bad/misc...reen_mars.html . Misleading your readers like this is gross incompetence. A freshman journalism student in college should have better fact-checking skills. Shame on you.

Edited to fix coding.

genebujold · #63 (**permalink**) 02-August-2004, 06:58 PM

Outstanding analysis, majic!

01101001 · #64 (**permalink**) 02-August-2004, 09:06 PM

The NASA Mars photojournal site has a nice recent example of one subject in natural vs. false colors. The two images are:

Two Holes in 'Wooly Patch'

Two Holes in 'Wooly Patch' (False Color)

Isn't it a pretty blue? Pity it's not real.

Irishman · #65 (**permalink**) 02-August-2004, 11:47 PM

FYI - I received a response from RedNova, including the following quote:

Quote:

"Certainly like the green in the Gusev crater picture or by looking at the development of darker spots toward the South Pole which are tied to seasonal variations, it certainly gives rise to the speculation that there could be algae." - Michael McKay, European Space Agency.

That was the extent of the quote provided to justify the article and that picture. There's no context provided for that quote, and I suspect the author saw that quote out of context - if they didn't deliberately misrepresent it. I do not think McKay is supporting the notion that those features represent life, but rather stating that they have been used to support speculation about life. Speculation not necessarily from within the science community. Without the proper context (i.e. more information about the quote, other comments made at the same time, the question it related to, the rest of the paragraph it is from, etc), it is unclear what that statement really meant.

I still think the statement is misrepresented, but I will pull back the full heat of my criticism.

frogesque · #66 (**permalink**) 03-August-2004, 12:53 AM

My understanding of the problem is that although colour perception is subjective rather than an exact science, what the photographs are doing is conveying digital information in a form that can be quickly interpreted by a human observer. We are familiar with all maner of charts and maps showing our own world in false colour. An atlas will show topographical details as colour contours from dark blue in deep oceans to white topped mountain ranges. In this scheme, low-lying deserts will be shown green. We have maps of the big bang echos showing different colours to enable visual representaion of temperatures that are so cold we coudn't re-create them with liquid hydrogen. Even the stock market gets coured red and blue and there is nothing more false!

Between 5% and 10% of the male population has some degree of colour blindness so why do we all get so excited about the "true colour" of Mars? As on Earth, local colour will depend on illumination, dust particle absorbtion and backscatering.

Yes, I agree it would be nice to look at a picture of Mars and be able to say, "Wow! What a pretty Martian sunset", but that isn't the main purpose of the photographs. They are taken to provide scientific data about the Martian environment, help asses the geology and aid navigation and exploration.

False colour or not, some of the images have been more stunning than a pinup calender (are those real girls or some sort of alien race?) and I would just like to say thanks to NASA for releasing all the pictures warts and all.

EDIT: I note I have [bad word deleted] in my post - seems as though I left an 's' off the end of 'assess'

ops:

lyford · #67 (**permalink**) 03-August-2004, 12:59 AM

Quote:

Originally Posted by Irishman

I'm "anti-green" in that I want the images as correctly balanced as possible, and all the evidence shows that bright greens and blues are color balance problems.

Irishman? Anti-green? Is it possible?

The ESA corrected themselves quite quickly, IIRC, but it was too late. The JPG was already out of the bottle.

The woo woos will use anything for ammo it seems, so best not to put out anything prematurely that needs to be corrected later - which of course just proves there is a cover up! Maybe NASA et al. need to embed a big watermark in each picture like they do with color chips from the paint store:

"Colors may vary. Use image for comparison only."

For them, a single data point (one press release photo that happens to appear to lend credence to their hopes "see green=life, told ya!") somehow trumps massive interlocking data sets that have accumulated over years of research.

The hidden-seen-too-many-x-files-episodes assumption is that someone accidently let the truth slip out, and now all the big bad scientific agencies are squelching the data so as not to threaten the established paradigm.

As if anyone remotely involved in these spaceflights wouldn't be chomping at the bit for conclusive proof of Martian life - can you say Nobel? Why on earth would any scientist want to cover that up??????

ToSeek · #68 (**permalink**) 03-August-2004, 01:15 AM

Quote:

Originally Posted by Irishman

FYI - I received a response from RedNova, including the following quote:

Quote:

"Certainly like the green in the Gusev crater picture or by looking at the development of darker spots toward the South Pole which are tied to seasonal variations, it certainly gives rise to the speculation that there could be algae." - Michael McKay, European Space Agency.

RedNova's statement is: "Scientists believe the green areas in this image from the Mars Express may be some form of life on the red planet."

1. They've only quoted one person.
2. Michael McKay is an engineer and operations manager for the spacecraft. He's not a scientist.
3. The quote is from Linda Moulton How, who has not struck me as a very reliable source.

Irishman · #69 (**permalink**) 03-August-2004, 10:37 PM

Ah, the trail becomes more clear. Linda Moulton Howe asks McKay a leading question regarding life on Mars (e.g "people seem to see features in the pictures that may be algae - tell us about that"), and McKay makes some explanatory comment that she extracts the part that sounds like it supports her position. Then the RedNova author reads her article and quotes her distorted quote, and misrepresents the qualifications of the original source to boot.

DJ Barney · #70 (**permalink**) 06-July-2007, 01:19 AM

"We all see what we want to see. You have to look with better eye's than that"

The Abyss

DaveC426913 · #71 (**permalink**) 06-July-2007, 05:25 AM

Holy drag-a-mummified-thread-out-of-a-perfectly-good-grave Batman...

Gotta be a record....

majic · #72 (**permalink**) 23-July-2007, 02:39 PM

....*stretches*... who disturbed my dusty grave !

DJ Barney · #73 (**permalink**) 23-July-2007, 02:51 PM

It was I ! I claim the power of this long lost tomb ! Now arise !

Ok, enough messing around.... I still think this is an important subject. I have missed many colour images mainly because of listening to some people whining on and ON about "where are the colour images". When they get them they are "the wrong colour", not that anyone has actually stepped on Mars, but anyway.

Check this thread .... the MER colour mosaics on this thread are truly ASTOUNDING ! They show what should really come out the end when you understand how to radiometrically adjust images, use the right channels, and many other factors. They seem so sharp as well.

DJ Barney

Mat Mason · #74 (**permalink**) 08-June-2008, 02:34 PM

Quote:

Originally Posted by Ian Goddard

Thanks for your insightful analysis Majic! This is an issue that should be addressed considering its popularity. I can't quite figure what the "true color" conspiracy theorists are seeing in terms of a devious motive to alter the color. It doesn't seem to make sense to me. But it is annoying that there is so much variation just for the simple reason that one should like to have as real a picture as possible. But this raises a deeper issue...

"True color" is somewhat more of a philosophical issue than many people may realize. Colors are not actually properties of the objects that appear colored. Colors are a perceptual end-product involving several intermediary steps from the frequency of reflected light, atmosphere, perceptual lenses (which as you note may include photos of photos before reaching the observes' own bio-optics), and interpretation. You raise some of the complexities in this process of processing. As an example, I've noticed that if you look at pumpkin-seed butter under incandescent light inside, it's dark brown; but then step outside and look at the same butter in sunlight (direct or indirect) and it's bright light green without any trace of brownness! It's the most remarkable color transition I can recall having observed in one substance and quickly demonstrates how color is not a private property of a thing but is instead a property distributed over all interacting environmental elements.

Another thing to consider in this case is that Mars as a whole seen from a distance can appear to be of a different color based on what time of the year it's observed. If my recall is correct this is due to seasonal sand storms that Carl Sagan was involved in determining. Long ago it was proposed that the seasonal color change of Mars was a signature of seasonal plant growth .

This may be a useful report: Solving the color calibration problem of Martian lander images.

Lets make this really simple....The problem with Mars color came all the way from Viking mission (1976) A reddish ski in the image but they forgot the American flag ...It was purple ...And also the Nasa logo colors they were wrong ......A conspiracy ? ....No way, to have a conspiracy some brains are needed....

Mat Mason · #75 (**permalink**) 08-June-2008, 02:41 PM

Quote:

Originally Posted by TriangleMan

So what exactly is going on here, are conspiracy woo-woos looking at Mars photos with different color calibrations and claiming that NASA is covering up aliens or something? :-?

No there were no woo woos ....There were only an American flag screaming ...I am not purple (Viking mission sticker and NASA logo...)

djellison · #76 (**permalink**) 09-June-2008, 12:18 AM

By all means demonstrate to us what you believe the actual colours of the Martian surface are.

Nowhere Man · #77 (**permalink**) 09-June-2008, 02:52 AM

Please note that this thread was started four years ago, and the last post before Mat Mason said something was a year old.

Fred

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