I Don't Believe in Imaginary Property brings us a Washington Post story which discusses how scientists are finding surprises among the pictures sent back from Mercury by the Messenger spacecraft. In particular, images depicting a crater with over 100 troughs radiating out from it are stumping researchers. The crater is referred to as 'The Spider', and it occupies a basin that has turned out to be larger than once thought. NASA also has a discussion of the crater. The Messenger craft began taking the up-close photos earlier this month. From the Post: "Scientists were also surprised by evidence of ancient volcanoes on many parts of the planet's surface and how different it looks compared with the moon, which is about the same size. Unlike the moon, Mercury has huge cliffs, as well as formations snaking hundreds of miles that indicate patterns of fault activity from Mercury's earliest days, more than 4 billion years ago."