Opportunity Sol 111 Fossil
This is a clear orderly structure that is not the result of mineral formation or erosion
| This small rock was
displaced when Opportunity ran over the edge of this loose stone
slab. As it tipped up, this rock (which was apparently flat in the
ground) broke free and angled up so that we can image it clearly.
You can clearly see the teardrop shapes radiating from the central "spine" feature. What are they? While they look like they might be from a plant, I suspect that this might be a larger marine organism, like a sand dollar or other simple echinoderm. Another likely explanation (and the one that makes the most sense to me) is that this is the root or base of a large crinoid. The teardrops are spaced at roughly 72° angles, which makes a pentagon. The three top teardrops are very clear. The other two (suspected teardrops) remain in shadow or broken off. If this fossil had remained in the ground, we would never have seen it. Imagine what other finds there are, waiting for the first shovel to turn them over. |
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| This marked-up view outlines the most obvious features. This is not some trick of light and shadow, as the next image will prove. |  |
As you can see from the above stereo image, there is no way that this is an illusion. The shape is solid across three dimensions and is proven to be real, not a trick of the eyes. This is a real fossil that no serious minded individual can challenge.
Compare the above stereo image to these terrestrial crinoid fossils (click each image for the original source).
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