Hours: Museum Mon.-Sat. 10-5, Sun. noon-5, Memorial Day weekend-Labor Day and during school vacation weeks; Mon.-Fri. 10-3, Sat. 10-5, Sun. noon-5, rest of year. Planetarium only open in summer. Hours vary; phone ahead. Closed Jan. 1, Easter, July 4, Labor Day, Thanksgiving, Christmas Eve and Christmas. Allow 1 hour, 30 minutes minimum.