With all the press surrounding Curiosity, you may have forgotten that we already have a working rover on the surface of Mars. Even though its sister rover Spirit has long since been consigned to its Martian grave, Opportunity is still roving around the red planet and returning valuable science data. Apparently unphased by the new kid on the block, Opportunity has just sent back some headline grabbing data of its own with a picture of a never before seen formation on the surface of Mars.
At first glance the new image looks like a variation on the Martian “blueberries” that Opportunity has seen lots of since it first landed in 2004. When they were first discovered, the spherical objects led to a lot of speculation about being a sign of life, but upon further inspection the “blueberries” proved to just be deposits that are formed by mineral rich water filtering through rocks and leaving behind the iron rich spherules. The new objects found by Opportunity are, however, not rich in iron and seem to be far softer than the previously seen “blueberries”. Opportunity’s principle investigator Steve Squyres of Cornell University is pretty excited by the rover’s find at the Kirkwood outcrop of Endeavor Crater.
This is one of the most extraordinary pictures from the whole mission. Kirkwood is chock full of a dense accumulation of these small spherical objects. Of course, we immediately thought of the blueberries, but this is something different. We never have seen such a dense accumulation of spherules in a rock outcrop on Mars.
Where broken apart by wind erosion these new spherules (dubbed the Kirkwood spheres after their location) appear to have concentric circle pattern inside. Although the team has several different theories on what made the spheres, they haven’t agreed on the most likely one yet. This new find is likely to keep the team occupied for a while before it goes to its next target, a nearby outcrop that contains evidence of clay minerals.
Whether or not this new find turns out to be a truly amazing discovery that tells us something we didn’t know about the history of Mars, I think the most amazing news is the fact that a little solar powered rover that was only supposed to last 90 days, is still roving around the surface of Mars and sending back pictures and data 8 years later. If that’s what a NASA budget and dust covered solar panels get you, it kind of makes you wonder how long the nuclear powered Curiosity rover is going to last.