NASA claims that new mysterious spheres discovered by the Mars Opportunity rover are puzzling researchers to no end. According to Opportunity's principal investigator, Steve Squyres of Cornell University in Ithaca, "this is one of the most extraordinary pictures from the whole mission."
Soon after Opportunity landed, it discovered similar spheres. The scientists nicknamed them blueberries and soon they discovered that they were rich on hematite. Those were evidence of a Mars' past full of water. But these spheres — which are 3 millimetres in diameter — are nothing like that.
Found in the Kirkwood outcrop, in the western rim of Endeavour Crater, these spherules' composition is completely different from the old Martian blueberries. Scientists still don't know how they got there and what they are supposed to be, says Squyres:
They are different in concentration. They are different in structure. They are different in composition. They are different in distribution. So, we have a wonderful geological puzzle in front of us. We have multiple working hypotheses, and we have no favourite hypothesis at this time. It's going to take a while to work this out, so the thing to do now is keep an open mind and let the rocks do the talking.
In the image you can also see spheres that have been eroded, showing a concentric internal structure. Researchers are now conducting more tests, trying to come up with an explanation on what these may be and how they got there.
But perhaps they already got the answer in Squyres' own words: "they seem to be crunchy on the outside, and softer in the middle." Obviously, Martians knew how to make chocolate Krispies cakes. [NASA]