Bay seniors who are tempted to check out their personal DNA or show their grandkids a robotic zoo, are encouraged to visit the vast Bay Area Science Festival which is in full swing from now until November 7. Scientists and technologists from labs and universities around the Bay Area whose minds are bubbling over with innovative ideas are participating in this public explosion of up-to-the-nanosecond scientific advances. Free events take place across the Bay Area. One of the high points is the Steam Carnival held November 6-8 from 10-4 at Pier 48 near the Ballpark. Expect aerialists, stage shows and interactive high tech games. $25-30.