A 48-year-old man dies Thursday after a crash on the interstate near Janesville.  The Wisconsin State Patrol reports an SUV was driving northbound on the interstate when it went off the highway at mile-marker 173.  The driver, who authorities say was from Prairie du Chien, died of his injuries.  The State Patrol is holding off on releasing his name until family is notified.  They are also investigating the cause of the crash.