The door is open to a wealth of knowledge opportunities at this day of exploration. Discover the vast solar system with all its suns, moons and planets at the Bell Museum's ExploraDome. Meet and play sports with University of Minnesota athletes. If you've dreamed of stardom, create your own short film. Other activities include make-and-take activities, language and music opportunities. (1-4 p.m. Sat., Van Cleve Park, 901 15th Av. SE., Mpls.

Dakota Family Day

Speakers and artists from the Dakota community will share their traditions. Performances by Bobby Wilson, Dallas Goldtooth and Jackie Bird. Learn words from the Dakota language and complete a craft. (Noon-4 p.m. Sat. Free. Minnesota History Center, 345 W. Kellogg Blvd., St. Paul. 651-259-3000.