Date of discovery: January 2014
Location of discovery: Mars
Sol 3528: http://marsrover.nasa.gov/gallery/all/opportunity_p3528.html
Sol 3540: http://marsrovers.jpl.nasa.gov/gallery/all/1/p/3540/1P442453196EFFCAEFP2594L2M1.JPG
Look at theses two close up photos of the surface of Mars. Both are the same except an object that was not there earlier has suddenly appeared from nowhere. Comparing Sol 3528 we see the object is gone, but later the photo of the area is taken again and the object is there.
I enlarged the object and it seems to be an odd shaped creature of some sort. In the enlargement you can also see that its sort of a square shape, but its center is pushed downward. It would be cool if this was some kind of crab-like creature. Very cool and please visit the source for the full story about it. SCW