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Wrong colors of Mars:

NASA pictures from Mars:

Mars is the "red" planet, as we know it. Red rocks, red sky, red clouds of sand, everything red. Is it really red? maybe not. Maybe the Mars pictures are just colorized red.

The reason for the colorization:

What was there to hide? Ron Levin mentions "rocks with greenish patches on them".

"Barnacle Bill":

Barnacle Bill

This is a extract of the original "Barnacle Bill" rock photographed by the Pathfinder lander. "Barnacle Bill" is a rock west-northwest of the Mars Pathfinder lander and was the first rock visited by the Sojourner Rover’s alpha proton X-ray spectrometer (APXS) instrument. Do I need to explained why it was the first visited rock? Do I need to comment on the name of the rock? Look at the bottom of the rock.

Barnacle Bill

A closer look at the bottom part of "Barnacle Bill".

First pictures by Viking II:

Viking II

This is the first color image of the Viking Lander 2 Site, NASA catalog number PIA00568, available at The picture has obviously already been colorized.

Viking II

After turning down again the red component, the picture looks like this. Of course, turning down the red color does not restore the missing other colors. If the green color for example has been removed, it will not appear again.

Viking II
Viking II

Nevertheless, in a lot of Viking pictures like this one, you will see a kind of brownish deposit on some rocks, not all. Is is some kind of lichen? Fungus? Maybe, maybe not. I raise the question.

But obviously you cannot raise the question if you look at the colorized pictures, because the possible lichen is not visible.

One more quote:

"Viking color images of the martian surface suffer from a variety of uncertainties, in particular the relative brightness of the "red" and "blue" channels. Early reconstructions of the Viking lander images tended to show "blue" sky, while later reconstructions, trying to account for out-of-band contributions in each filter, tended to show a "red" sky, and often an "orange" surface. Owing to calibration uncertainties, the exact reconstruction of Viking Lander color images remains more or less an art. Recognizing that even white portions of the spacecraft will appear slightly pink (or apricot), since sunlight reaching the surface is filtered through the atmosphere, which has a fairly high concentration of dust, and further recognizing that "orange" is not a particularly prevalent geologic "color," the colors in these reproductions tend more towards reddish-browns."

Let's not even mention the fate of the green color...

Do not trust me, check on the Viking Lander Marslink Page at the Malin Space Center web site at

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This page was last updated on March 24, 2001.