Some of the most dedicated star and planet gazers in the country will be in St. Paul this weekend for the annual astronomical society conference. One topic they'll be considering- Mars. The red planet is brighter in our southern skies this summer than it has been in 13 years. Bill Sheehan is an amateur astronomer who is an expert on Mars and a featured speaker at the conference. Sheehan says Mars is one of the most visible objects in the sky, which could explain the long-standing human fascination with it: