A Traveler's Guide to Mars: Don't leave orbit without it! William Hartmann's new book contains a terrific collection of Mars images, some taken as recently as a few months ago. A Traveler's Guide to Mars is much more than a Martian photo album. You'll hear about Hartmann's personal journey, and his top three picks for places to see. Emily Lakdawalla is once again following the water on the red planet, and Bruce Betts wraps up last week's Mars Day activities.