Posted on 10/01/2009 11:32:25 AM PDT by The Comedian
NASA's MESSENGER spacecraft is receding from Mercury after a Sept 29th flyby that put smiles on the faces of mission scientists. MESSENGER is beaming back images of thousands of square miles of previously unseen terrain, including this cheerful crater:
The arc-shaped depression in the crater's floor is a "pit crater." A few of these have been seen on Mercury, and they are probably volcanic in nature. Pit craters may have formed when subsurface magma drained away and left a roof area unsupported, leading to collapse and the formation of the pit. In this example, the southern area of the pit appears to have two or more floor levels. The discovery of multiple pit-floor craters adds to a growing body of evidence that volcanic activity was widespread in Mercury's past.
Always cool. I think Kevin Davis is on a trip but I’ll ing him anyway.
Obviously proof of a now long-extinct Hermian civilization, who left this smiley-face as a jesture of an abiding sense of humor, even in the midst of a tragic demise.
The discovery of multiple pit-floor craters adds to a growing body of evidence that volcanic activity was widespread in Mercury's past.And when the surface is studied in detail (robotic mission to the surface, and then maybe a human crew someday) it will be shown to be nearly entirely the result of impact, same as the Moon, same as Mars.
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