David Grinspoon (author of Venus Revealed and Lonely Planets) review of Roving Mars and Dying Planet in the November, 2005 issue of Scientific American:

http://www.sciam.com/article.cfm?chanID=sa006&articleID=0008B5F8-0B30-1354-8B3083414B7F0000&colID=12

Excerpts:

"Two recent books come at the planet from very different perspectives. In Roving Mars, Steve Squyres gives us a vivid, intimate travelogue of the spectacularly successful (and as of this writing, ongoing) mission of the Mars Exploration Rovers, for which he serves as principal investigator. Robert Markley's Dying Planet takes a more distant view of the human relationship with Mars. An English professor at the University of Illinois, Markley writes about Mars science as a knowledgeable outsider, weaving in cultural history and science fiction."

"Markley might have a field day with some of the language in Roving Mars. Squyres seems obsessed with finding a "water story," even to the point of repeatedly implying that the success of each rover's mission hinges on finding concrete evidence of rocks formed in or altered by liquid water. Now of course, "following the water" is important for figuring out the natural history of Mars and whether it might have been more life-friendly in the past. But isn't a robot geologist, especially the first one on a new world, successful if it simply learns any story the rocks have to tell? It doesn't seem quite right to launch an investigation committed to finding a certain answer. Even less so when that answer, "Yes, there was water here, at some uncertain time and for some uncertain duration," basically confirms the paradigm that has been developing since 1971, as Mariner 9 and subsequent orbiters have provided images and global maps showing abundant evidence for flooding and channel formation. Ultimately the tremendous success of this mission goes much deeper than a simple verification of this widespread belief. Mars has myriad stories to tell. If water is what we seek, then that's what we'll find."

"It is obvious that Squyres knows all this, so why the dumbed-down rhetoric, where success is equated with proving a certain hypothesis? This is, in part, playing along with a certain line that NASA is using to package our current Mars exploration program. "Follow the Water" makes a fine slogan, and it does capture the essence of the questions of comparative planetology and habitability, both past and future, that form the core goals of our Mars program. Yet the actual motivations and strategies are never that simple. Given Squyres's admirable candor in addressing other aspects of NASA politics, I was surprised to see him uncritically adopt what seems like a simplified motivational mantra when describing the success criteria for his complex, multifaceted mission. Maybe he's just haunted by Lowell's ghost."