Fleeting Innocence, a sculpture consisting of thousands of interwoven latex balloons, creates intrigue Tuesday in the lofty conservatory of the Museum of Fine Arts, St. Petersburg. Jason Hackenwerth's work is expected to remain up for a couple of weeks. The New York artist says his balloon works evoke joyful memories and, like our bodies, are ephemeral, reminding us "to be present in the moment." The museum, at 255 Beach Drive NE, will have a free "porch party" from 5:30 to 7 p.m. Thursday. Members get free admission to galleries till 8 p.m.; nonmembers pay $5. Also, get in every Thursday after 5 for $5.