I haven't got a clue as to what this could be, just pointing it out.
It has a dark 'head' and 'wings'.
Posted: October 19, 2007 12:24 PM
I went to the MER analysts notebook and got a higher res PNG and a bitmap of this frame.
It appears the lower wing is just a jpeg artifact, perhaps it is an airborne dust mote close to the lens, but it still has a tail on it.