One of the University of Iowa’s top space physicists is giving a talk in Iowa City tonight about the landmark progress being made in the search for water on Mars. Dr. Don Gurnett’s free lecture at 7:30 P.M. in Van Allen Hall will include a summary of theories dating back to the 1880s about canals being seen on Mars, the “proof” found in 1907 that “conscious, intelligent life” exists on Mars, and H-G Wells’ 1938 “War of the Worlds” broadcast. Then, he’ll move from science fiction to science facts to discuss why finding water on Mars is so important.He says there’s “very compelling evidence that there’s been a lot of water (on) Mars in the past.” Astronomers have long studied Mars’ dry river beds from afar, but now one of NASA’s rovers has found hematite (HE’-mah-tite), an iron ore that only forms in the presence of water. He says if people ever get to the Red Planet, water will be vital — since humans need it to stay alive, to cook with, to bathe in, to grow plants, and more. If water’s already there, astronauts wouldn’t have to take along a big supply. Gurnett is a veteran of more than 30 major spacecraft projects, including Voyagers 1 and 2, the Galileo mission to Jupiter and the Cassini mission to Saturn. Gurnett says hematite is the latest clue in the quest for Martian water, which is key to life as we know it. He says water is also important to future manned missions as it can be electrolyzed, broken down into its hydrogen and oxygen components, and used as rocket fuel for the return home. A probe called Mars Express, designed and built in part at the U-of-I and already in Mars orbit, will soon use a special type of radar to prospect for water three miles below the Martian surface.