Granicus Valles and Tinjar Valles"On August 27, 2003, the orbital paths of Earth and Mars brought them to within 34.65 million miles of one another -- closer than at any other time in the past 50,000 years. Though Mars never actually appeared "as large as the full moon to the naked eye," the red planet did vividly dominate the night sky for a time, making 2003's "close encounter" a "once in a lifetime" event indeed for astronomers, space enthusiasts, and ordinary observers alike.
Nothing so spectacular is predicted for 2006."
http://www.esa.int/esaCP/index.html
http://urbanlegends.about.com/library/bl_mars_encounter.htm