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Old 25-March-2008, 09:55 PM
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Originally Posted by Hornblower View Post
Mariner 10 did not take any color photos, according to an article by Andrew T. Young of San Diego State University, published in Sky and Telescope, May, 1985.

In that article he provided swatches of color for most of the planets, along with the Moon, Io and Titan. The swatches were generated from reflectance spectra that were not subject to the limitations of many of the spacecraft.

I will go into it more in a later post, and I will try to scan and upload the swatches.

The swatch for Mercury was much browner than the neutral gray on the black-and-white image shown in the linked page. Let me add that those pages make no claims about the accuracy of color rendition.
Thanks. I should have qualified them. It took a while to make the link list as I went through every APOD image. Ug. By the time I found all that I could, I had forgoten I had even claimed they were near to true color, though that had been my objective.

The APOD link I gave for Mercury, however, is not a typical false color image, at least in any dramatic way. [I know what little color is there is important for scientific study, so l do want to remind others that true color is not much of a great scientific goal. Getting close to true, or natural, color is more valuable for PR and art, than science.] The image may still prove to be pretty close to true color since it is so gray, typical of what we should expect. Is this likely?

In the last hour, I stumbled into the latest from Messenger. I found it on Astronomy's next cover issue, as is shown on their website. Here is one image that may or may not be indicative of what one might see in natural color. It is tempting to think it might be close.

Messenger's MDIS package (one narrow and one wide angle camera) uses 11 filters, which, as they put it, allows them to see "much like our eyes do", though no specific image mentions such a case. It would surprise me to see a near true color image actually reveal much color at all.
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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.
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