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Are There Artifacts on Mars?

Table of Contents
Introduction
What Color is Mars? The Green Planet? The Glass Worm
Face the Face City Slicker The White Bunny
Bizarre Image Analysis Say What? (Updated March 24, 2004) Hoagland's Credentials
NEW! (March 13, 2004) Some fallout: Hoagland discusses these pages on C2C
Conclusions
Links of Interest

Hoagland's stock in trade is in grossly misinterpreting images, usually by taking compressed JPEGs and then enlarging them beyond their resolution. Sometimes he just looks at images and, it seems, makes stuff up out of thin air. Hoagland wrote a whole book on the "Face" on Mars, when it is really just a hill. But he does this over and over again, with many such images. How does this work?

Let's take a look at digital images. When you take an image with a digital camera, the file size can be huge. Mine typically takes 300-400 kilobyte images. However, you can compress the file size of the image using various mathematical techniques. JPEG is actually a technique that can compress the file size of images to various degrees. The more you compress the file size, the worse the image looks.

Take a look at the images below. The image on the left is a JPEG of me saved at medium compression. Click on it to get the full-resolution image if you want to see the nicest quality (it's about 70kb). The image on the right was saved with maximum compression. The image looks awful. Straight lines in the higher-res image look crooked, or wavy. Curves become blocky; colors get oddly mixed.


magnified low-res picture of my eyes To make things worse, literally, I cropped the original high-resolution image to just show my right eye, resized it to twice its original size, then saved it at maximum compression. Look how awful the quality is. You can see all sorts of wiggles and weird features around my glasses. None of that is real, as you can see in the high-resolution image. They were all introduced when I compressed the image.

Hoagland's website is full of images like this. He takes images, blows them up, saves them as JPEGs, then claims there are patterns in them indicating regular structures! Here is one he claims shows a building. Here is another with a "power plant". In fact, this long, rambling webpage on Hoagland's site has many such examples of over-magnified, over-compressed images showing compression noise. They are not artificial structures, as he claims, they are simply what you get when you over-manipulate an image, as I did above.

I'll add that he has claimed that the "Face" on Mars has teeth in it. It doesn't; once again the "teeth" are due to bad image processing.

Really, that's all there is to many of his claims of artificiality. They are artifacts, all right, but not in the sense of man- (or alien-) made items; they are image artifacts, and not real at all.

He does make other claims of artificiality, not necessarily based on over-blown-up images, but in the end he's wrong about those as well.



©2008 Phil Plait. All Rights Reserved.

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