These Dunes Are the Pits. Or Vice Versa.

I love a good coincidence. Especially a series of them. To wit: Last week I wrote an article about a massively viral optical illusion photo of a brick wall--if you haven't seen it yet, I won't spoil it; just go to my post and be amazed. The very next post I put up after that had images taken by the Dawn spacecraft of the protoplanet Ceres, showing the cratered surface. The funny thing is I got a few emails and tweets from people saying they were seeing the craters not as depressions in the surfa...