Now, don't misunderstand me and think that the Spirit rover on Mars hasn't grabbed my interest. In a funny coincidence, I opened up a text on geology two weeks ago and in free time since have been acquainting myself with the wonderful world of silicate minerals as described in early chapters. What can speak volumes of Mars' past and present? Geologic conditions, that's what. So I've done a little peeking and stumbled on this article, which would have been a mouthful of technical rock-talk had I not done a little preliminary reading. Because I have, it's only partially overwhelming, and otherwise tonic for the imagination. Feldspar! Olivine! Aqueous mineralization!
In turn, that's raised my expectations for Spirit - the media blitz of these initial snapshots will be far from the most interesting finds of the mission.