The 2005 North American Solar Challenge (NASC) was an intercollegiate solar car race on July 17–27, 2005. The event was won by the University of Michigan, with the University of Minnesota finishing less than 12 minutes behind them, in what was both the longest and most closely contested race in the history of the event. The race was notable for being the first solar car race to cross an international border. It was the 8th American national championship solar car race held.